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Dedicated to the military history and civilization of the Eastern Roman Empire (330 to 1453)


"Time in its irresistible and ceaseless flow carries along on its flood all created things and drowns them in the depths of obscurity."

- - - - Princess Anna Comnena (1083–1153) - Byzantine historian

Showing posts with label Balkans. Show all posts
Showing posts with label Balkans. Show all posts

Tuesday, October 26, 2021

Justiniana Prima - Roman Fortified City


Remnants of the city of Justiniana Prima


Defending The Roman Balkans
The City-Fortress of Justiniana Prima



In the centuries after the fall of the Western Roman Empire it is hard to believe that there were any people at all left in Central Asia - - - just about every tribe imaginable marched southwest and invaded the Eastern Roman Empire.

By the year 500AD the entire northern bank of the Danube from Belgrade to the Black Sea was occupied by one Slavic tribe or another. Why these tribes showed up no one knows. But in their desire for loot, slaves or land they put mounting pressure on the Roman frontier. Two of the earliest Slavic tribes were the Antes and the Sclaveni.

Justiniana Prima was one of the many fortified cities founded by the Emperor Justinian to help stabilize the Balkan frontier. The city existed from 535 to 615 near modern Lebane in southern Serbia. The city served as the metropolitan seat of the Archbishopric of Justiniana Prima, that had jurisdiction over the provinces of the Diocese of Dacia.

The city was a completely new foundation in honour of the nearby village of Tauresium, the birthplace of Justinian. According to Procopius Bederiana, the birthplace of Justinian's uncle and mentor Justin I was nearby.

Justinian himself ordered the foundation of the city by law in 535, establishing the Archbishopric of Justiniana Prima, making it at the same time the capital of the prefecture of Illyricum instead of Thessaloniki (although this is disputed among historians). 

Justinian made sure that this city, which was one of his favorite projects, received all the necessary support.

"He therefore built a wall of small compass about this place in the form of a square, placing a tower at each corner, and caused it to be called, as it actually is, Tetrapyrgia. And close by this place he built a very notable city which he named Justiniana Prima, thus paying a debt of gratitude to the home that fostered him. In that place also he constructed an aqueduct and so caused the city to be abundantly supplied with ever-running water. And many other enterprises were carried out by the founder of this city - works of great size and worthy of especial note. For to enumerate the churches is not easy, and it is impossible to tell in words of the lodgings for magistrates, the great stoas, the fine marketplaces, the fountains, the streets, the baths, the shops. In brief, the city is both great and populous and blessed in every way."
Procopius' description of Justiniana Prima in The Buildings.


The town was abandoned at around 615. Invading Avars coming from north of the Danube may be one factor, missing political interest in the town after the time of Justinian may be another. 



Recreation of Justiniana Prima



Contemporary Historian Procopius:

Thus did the Emperor Justinian fortify the whole interior of Illyricum. I shall also explain in what manner he fortified the bank of the Ister River, which they also call the Danube, by means of strongholds and garrisons of troops. 

The Roman Emperors of former times, by way of preventing the crossing of the Danube by the barbarians who live on the other side, occupied the entire bank of this river with strongholds, and not the right bank of the stream alone, for in some parts of it they built towns and fortresses on its other bank. However, they did not so build these strongholds that they were impossible to attack, if anyone should come against them, but  they only provided that the bank of the river was not left destitute of men, since the barbarians there had no knowledge of storming walls.  

In fact the majority of these strongholds consisted only of a single tower, and they were called appropriately "lone towers," and very few men were stationed in them.  At that time this alone was quite sufficient to frighten off the barbarian clans, so that they would not undertake to attack the Romans.  But at a later time​ Attila invaded with a great army, and with no difficulty razed the fortresses; then, with no one standing against him, he plundered the greater part of the Roman Empire.  

But the Emperor Justinian rebuilt the defences which had been torn down, not simply as they had been before, but so as to give the fortifications the greatest possible strength; and he added many more which he built himself.  In this way he completely restored the safety of the Roman Empire, which by then had been lost.


A recreation of a "single tower" Roman fortification.


Justiniana Prima in 1937. Photo archive of the 
Military Geographical Institute of Serbia.

Justiniana Prima





Endless Slavic tribes pounded the Roman 
fortifications in the Balkans.

The Collapse of the Roman Empire
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By 650 AD (map above) the Balkan Roman frontier was in complete collapse with Slavic tribes advancing all the way to southern Greece. 

The first appearance of the Slavs in the Eastern Roman Empire can be dated no earlier than the 6th century. Throughout this century, beginning with the reign of Justinian, Slavs repeatedly invaded the Balkan possessions of the Empire. Not until the reign of Maurice, however, did any Slavs settle in these territories. Between the years 579-587 there took place the irruption of several barbarian waves led by the Avars, but consisting mostly of Slavs. The latter came in great numbers, and, as the troops of the Empire were engaged in the war with Persia, they roamed the country at will.

Slavs devastated Illyricum and Thrace, penetrated deep into Greece and the Peloponnesus, helped the Avars to take numerous cities, including Singidunum, Viminacium (Kostolac), Durostorum (Silistria), Marcianopolis, Anchialus, and Corinth, and in 586 laid siege to the city of Thessalonica, the first of a series of great sieges which that city was destined to undergo at their hands. What is more, they came to stay.


(Procopius Buildings)    (unesco)    (Justiniana)

(panacomp.net)    (justiniana-prima.blogspot.com)


Saturday, June 15, 2019

Barbarians at the Gates - The Roman Balkans


Roman Reenactor
Marco le Méro Photographie is with Gwendal Lazzara at Funkenburg Westgreußen

The Coming of - Just About Everyone


In the centuries after the fall of the Western Roman Empire it is hard to believe that there were any people at all left in Central Asia - - - just about every tribe imaginable marched southwest and invaded the Eastern Roman Empire.

By the year 500AD the entire northern bank of the Danube from Belgrade to the Black Sea was occupied by one Slavic tribe or another. Why these tribes showed up no one knows. But in their desire for loot, slaves or land they put mounting pressure on the Roman frontier. Two of the earliest Slavic tribes were the Antes and the Sclaveni.

The history of the Eastern Empire in the 500s is dominated by the re-conquest of Roman lands by the Emperor Justinian (r. 527-565). All of Italy, North Africa, Southern Spain, Sicily and Sardinia once again were part of the Empire. But these new lands brought a serious military strain to the country: endless wars in all directions from invaders.

While the Roman armies were fighting in Italy, North Africa and against the Persian Empire the Slavs were crossing the Danube into the heart of the Roman Balkans.

The earliest inroads by the Slavs came under Justin I (518-527). But under Justinian the floodgates began to open. As powerful a threat as the Persians were, it was on the Danube, not the Euphrates, that the fate of the Empire was decided.

  • Contemporary historian Procopius:  "Illyricum and all of Thrace, that is, from the Ionian Gulf to the suburbs of Constantinople, including Greece and the Chersonese (the Gallipoli peninsula) were overrun by the Huns (the Bulgars), Sclavini and Antes almost every year, from the time when Justinian took over the Roman Empire; and intolerable things they did to the inhabitants."

At first these annual raids were for loot, after which the barbarians retired over the Danube.

Then in 540 the Kutrigurs delivered a shattering attack capturing 32 fortresses in Illyriccum on the west coast and plundering the countryside all the way to the suburbs of Constantinople. In 545 the Slavs plundered Thrace. Repulsed by Justinian's famous general Narses. they returned five years later coming within 40 miles of Constantinople, defeated a Roman army at Adrainople until finally being turned by at the walls of Constantinople itself.

By 550 things began to change. The raids became longer and the Slavs started to capture cities and fortresses often holding them for several years.

In 559 a Kutrigur-Slavic army crossed the frozen Danube and marched into Thrace. There it divided into sections. One marched into Thessaly where they were turned back by the Roman defenses at the defile of Thermopylae. A second attacked and was defeated at Gallipoli.

The third attacked the walls of Constantinople and laid waste to the suburbs. The Emperor recalled an aged General Belisarius. He forced the barbarians to retire beyond the Long Wall. A Roman fleet was simultaneously reinforced on the Danube cutting off the retreat of Slavs. Caught between two fires the Kutrigus sued for peace and returned to the steppes. This strategy would be used by the Romans many times over the years.

Map of Slavic peoples of the 6th century

Roman – Persian War of 572–591
Roman Wars on Four Fronts
The Roman armies faced a major war with the Persian Empire in the east.  At the same time they face invasion in the Balkans by the Avars, the invasion of Italy by the Lombards and a North African war against the Berbers.

Central and Eastern Europe about 650AD
The first appearance of the Slavs in the Eastern Roman Empire can be dated no earlier than the 6th century. Throughout this century, beginning with the reign of Justinian, Slavs repeatedly invaded the Balkan possessions of the Empire. Not until the reign of Maurice, however, did any Slavs settle in these territories. Between the years 579-587 there took place the irruption of several barbarian waves led by the Avars, but consisting mostly of Slavs. The latter came in great numbers, and, as the troops of the Empire were engaged in the war with Persia, they roamed the country at will.

Slavs devastated Illyricum and Thrace, penetrated deep into Greece and the Peloponnesus, helped the Avars to take numerous cities, including Singidunum, Viminacium (Kostolac), Durostorum (Silistria), Marcianopolis, Anchialus, and Corinth, and in 586 laid siege to the city of Thessalonica, the first of a series of great sieges which that city was destined to undergo at their hands What is more, they came to stay.

The Balkan Limes

The extent to which the Emperor Justinian neglected the Balkan Limes should not be exaggerated. The historian Procopius lists over 600 fortresses that were either built or restored by the Emperor.

Some of these were no doubt little more than fortified watch towers. Others may have never gotten beyond the planning stages. Even allowing for this the building was impressive. The old Roman limes were built along the Danube. Justinian's defenses formed a system of three fortified parallel belts - more of a defense in depth.

The first belt followed the natural barrier of the Danube River. Roman cities on the south bank such as Singidunum and Novae were strengthened to withstand invasions.

The second fortified line was just to the south. It stretched west to east in Roman provinces like Upper Moesia and Dacia Ripensis.  Some 107 strongholds were built or re-build. This zone also helped guard passes over Balkan mountains.

The third fortified zone was deep in the interior. It guarded the provinces of Haemimontus and Thrace, along with areas of eastern Serbia and western Bulgaria. A network of fortifications was strengthened or built.

It is believed that in many cases Justinian's fortifications were not built to last. As the tempo of barbarian invasions picked up in the last half of the 500s the Emperor's fortresses were obliterated and forgotten to such a degree that historians have problems with their locations.

In many ways Justinian cannot be blamed. From any point of view defending the massive Roman Empire stretching from Spain and Morocco to Switzerland to the Sahara Desert to the Balkans and the Euphrates was close to impossible. The manpower and money were just not there.

Reconstruction of a UNESCO limes fortress in Germany. Due no doubt to budgets, most of the Roman limes defenses along the Danube were much weaker - often little more than watchtowers like the one below.


Roman forts along the Danube limes - theoretical reconstruction


The Empire might not have been able to turn back many of the invading Slavic armies, but then there was the old standby of using money and diplomacy.

To relieve pressure on the Danube, Justinian used a combination of military pressure, economic cajolery and religious propaganda to divide and control the different tribes.

For example in 530 a certain Slavic chief of great ability named Chilbudius was enticed into Roman service. He was appointed supreme commander on the Danube which he successfully defended for several years against the Kutrigurs, Antes and Sclavini. In 535 Justinian offered the Antes money and lands on the northern bank of the lower Danube. The tribe was granted the status of Foederati on condition they would hold the river against the Bulgars.

This policy worked for for and against the Empire. The Romans had gained allies to defend the frontier but at a great drain on the Imperial Treasury and widespread discontent among the people. Also paying out money to barbarians just attracted more barbarians.

  • Procopius:  "For these barbarians, having once tasted Roman wealth, never forgot the road that led to it . . . . Thus all the barbarians became masters of all the wealth of the Romans, either being presented with it by the emperor, or by ravaging the Roman Empire, selling their prisoners for ransom, and bartering for truces."

The Coming of the Avars

In the last years of Justinian's rule the Central Asian Avars appeared in Constantinople. Their leaders were placated with presents of gold chains, saddles and silk robes. A treaty was concluded where the Avars would defend the Empire. But as foederati they did their job too well defeating enemies everywhere.

Tired of paying out money in 565 the new Emperor Justin II haughtily rejected an Avar delegation's request for tribute. Shortly thereafter began a 58 year long series of wars with the Avars.

The Avars usually raided the Balkans when the Roman Empire was distracted elsewhere, typically in its frequent wars with the Sassanid Empire in the East. As a result, they often raided with impunity for long periods of time, before Roman troops could be freed from other fronts to be sent on punitive expeditions. This happened during in the 580s and 590s, where Byzantium was initially distracted in the Byzantine–Sasanian War of 572–591, but then followed up by a series of successful campaigns that pushed the Avars back.

The Avars almost launched a massive attack on Sirmium in 568, but were repulsed.

The Romans paid them 80,000 gold solidi a year. Except for a raid on Sirmium in 574, they did not threaten Byzantine territory until 579, after Tiberius II stopped the payments. The Avars retaliated with another siege of Sirmium. The city fell in c. 581, or possibly 582. After the capture of Sirmium, the Avars demanded 100,000 solidi a year. Refused, they began pillaging the northern and eastern Balkans, which only ended after the Avars were pushed back by the Byzantines from 597 to 602.

Avar mounted archer

Avar warriors
(pinterest)

Charge of the Avars taken May, 2011.
(flickr.com)


The flavor of the times, the helplessness of the Empire to defend the Balkans, is captured by Syriac historian John of Ephesus in 584.

  • "That same year, being the third year after the death of King Justin, was famous also for the invasion of an accursed people, called the Slavonians, who overran the whole of Greece, and the country of the Thessalonians, and all Thrace, and captured the cities, and took numerous forts, and devastated and burnt, and reduced the people to slavery, and made themselves masters of the whole country, and settles it by main force, and dwelt there in it as though it had been their own without fear. And four years have now elapsed, and still, because the king is engaged in a war with the Persians, and has sent all his forces to the East, they live in the land, and dwell in it, and spread themselves far and wide as God permits them, and ravage and burn and take captive. And to such an extent do they carry their ravages, that they have even ridden up to the outer walls of the city (i.e. the Long Wall of Constantinople), and driven away all the king's herds of horses, many thousands in number, and whatever else they could find.  And even to this day . . . . (584) they still camp and dwell there, and live in peace in the Roman territories, free from anxiety and fear, lead captive and slay and burn: and they have grown rich in gold and silver, and herds of horses, and arms, and have learnt to fight better than the Romans . . . . "

After the end of the Roman war with the Persians in 591, Emperor Maurice shifted his focus to the Balkans. Maurice deployed veteran troops to the Balkans, allowing the Byzantines to shift from a reactive strategy to a pre-emptive one. The general Priscus was tasked with stopping the Slavs from crossing the Danube in spring 593. He routed several raiding parties, before he crossed the Danube and fought the Slavs in what is now Wallachia.

After years of offensive warfare the Romans pacified the Balkans for the first time since the reign of Anastasius I (r. 491–518). Maurice planned to repopulate the devastated lands which the Byzantines had recovered by settling Armenian peasants, as well as Romanizing the Slav settlers already in the area. Maurice also planned to lead further campaigns against the Avar Khaganate, so as to either destroy them or force them into submission. However, Maurice was overthrown in 602 by Phocas, as his army rebelled at the endless Balkan campaigning. Phocas promptly scrapped those plans.

The Avars, who were likely encouraged by their successful campaigns against the Lombards in 610 and the Franks in 611, resumed their incursions some time after 612. By 614, with the Persian capture of Jerusalem, it became clear to the Avars and their Slav subjects that retaliation from the Byzantines was extremely unlikely. Chronicles of the 610s record wholesale pillaging, with cities such as Justiniana Prima and Salona succumbing. The cities of Naissus and Serdica were captured in 615, and the cities of Novae and Justiniana Prima were destroyed in 613 and 615, respectively. 

The Slavs also raided in the Aegean, as far as Crete, in 623. During this time period, there were three separate sieges of Thessalonica: in 604615, and 617. In 623 the Byzantine emperor Heraclius journeyed into Thrace in an attempt to agree peace with the Avar Khagan face to face. Instead the Byzantines were ambushed, with Heraclius narrowly escaping and most of his bodyguard and retainers being killed or captured. 

Avar power peaked culminating in the Siege of Constantinople in 626.

The Persian king Khosrau II, after suffering reverses through Heraclius' campaigns in the Persian rear, resolved to launch a decisive strike. While general Shahin Vahmanzadegan was sent to stop Heraclius with 50,000 men, Shahrbaraz was given command of a smaller army and ordered to slip by Heraclius' flank, and march for Chalcedon, a Persian base across the Bosporus from Constantinople. Khosrau II also made contact with the Khagan of the Avars to allow for a coordinated attack on Constantinople, the Persians on the Asiatic side, and the Avars from the European side.

The Avar army approached Constantinople from Thrace and destroyed the Aqueduct of Valens. Because the Byzantine navy controlled the Bosporus strait, the Persians could not send troops to the European side to aid the Avars, which deprived the Avars of the Persian expertise in siege warfare. Byzantine naval superiority also made communication between the two forces difficult.

The Byzantine defenders had 12,000 well-trained cavalry troops, who were likely dismounted, facing roughly 80,000 Avars and Sclaveni (Slavs whose land was controlled by the Avars). Because the Persian base in Chalcedon had been established for many years, it was not immediately obvious that a siege would take place. It only became obvious to the Byzantines after the Avars began to move heavy siege equipment towards the Theodosian Walls.

On August 7, a fleet of Persian rafts ferrying troops across the Bosporus to the European side were surrounded and destroyed by the Byzantine fleet. The Sclaveni then attempted to attack the Sea Walls from across the Golden Horn, while the Avars attacked the land walls. However, the Sclaveni boats were rammed and destroyed by the galleys of Bonus, and the Avar land assaults on August 6th and 7th were repelled.

Even though the Persian army of Shahrbaraz still remained at Chalcedon, the threat to Constantinople was over, as the Persians could not use artillery from their side of the Bosporus.

After failing to capture Constantinople, the Avar nation rapidly began to decline before disintegrating entirely.

Roman Reenactor



The "De-Romanization" of the Balkans

The permanent colonization of Greece and other provinces by pagan Slavic tribes basically shattered the old Roman Balkans nearly beyond repair.

Latin and Greek were largely replaced by assorted barbarian languages. Christianity was replaced by pagan faiths.

In the West the German foederati looked to have a legitimate place and land within the Empire. The invading Slavic tribes destroyed nearly everything they came in contact with.

  • Cities were sacked. 
  • Large areas of the countryside were laid waste and were turned, in the words of Procopius, into a "Scythian wilderness". 
  • The Roman governmental machinery totally collapsed.
  • The network of bishoprics established in the 300s were almost wholly uprooted. Christianity was virtually extinguished for several centuries.
  • Entire stretches of the countryside were emptied of their inhabitants. Those who survived the slaughter were deported north of the Danube.


Long Term Military Impact - For centuries the Prefecture of Illyricum had produced some of the best soldiers for the Roman Army. With the massive genocide Illyricum was all but eliminated as a source of conscripts. The generals in Constantinople turned to Armenia and the Caucasus to fill the ranks.

By turning east for new officers and soldiers the Empire became more and more Asian in politics and orientation and less European. The late sixth century marks the rise of Armenians in government and the military.

From Magister Militum
 Heavy infantryman of the Ioviani Seniores, equipped with a long thrusting spear, lenticular shield and a heavy mail shirt alongside his helmet and thick, military belt. 

The Slow Roman Re-Conquest of the Balkans

To say the generals and Emperors had their hands full is an understatement.

No sooner was the Avar siege of Constantinople defeated and the Persian Empire totally crushed that they saw the rise of militant Islam.

Within a few decades the Roman provinces in North Africa, Egypt, Palestine and Syria fell to the Muslims. Trying to regain control of the Balkans was about as low on their list as it could get.

But re-conquer the Balkans they did - slowly, inch by inch.

The military theme system first appeared in the early 7th century, during the reign of the Emperor Heraclius, and as the Roman Empire recovered, it was imposed on all areas that came under Byzantine control. 

In their origin, the first themes were created from the areas of encampment of the field armies of the East Roman army, and their names corresponded to the military units that had existed in those areas. 

The first Balkan theme created was that in Thrace, in 680 AD. By 695, a second theme, that of "Hellas" (or "Helladikoi"), was established, probably in eastern central Greece.

It was not until 100 years later that a third theme would be established. 

In 782–784, the eunuch general Staurakios campaigned from Thessaloniki, south to Thessaly and into the Peloponnese. He captured many Slavs and transferred them elsewhere, mostly Anatolia. However it is not known whether any territory was restored to imperial authority as result of this campaign, though it is likely some was. 

Sometime between 790 and 802, the theme of Macedonia was created, centered on Adrianople. A serious and successful recovery began under Nicephorus I (802–811). In 805, the theme of the Peloponnese was created.

In the 9th century, new themes continued to arise, although many were small and were carved out of original, larger themes. New themes in the 9th century included those of ThessalonicaDyrrhachiumStrymon, and Nicopolis. From these themes, Byzantine laws and culture flowed into the interior. 

By the end of the 9th century most of Greece was culturally and administratively Greek again. But above Greece when the Emperor reconquered a province he would be ruling over Slavs - - - not Romans.

The re-Hellenization process begun under Nicephorus I involved (often forcible) transfer of peoples. Many Slavs were moved to other parts of the empire, such as Anatolia and made to serve in the military. In return, many Greeks from Sicily and Asia Minor were brought to the interior of Greece, to increase the number of defenders at the Emperor's disposal and dilute the concentration of Slavs. 

Hanging on by its fingernails the Roman Empire had survived the horrors of the Slavic, Persian and Muslim invasions of the 500s to the 700s. Latin vanished and Greek became the official language.

Moving forward the Empire was more of a fusion Greek-Armenian state than Roman.

Photo From Magister Militum
Roman reenactor


The Byzantine Commonwealth: Eastern Europe, 500-1453 by Dimitri Obolensky

(Avar-Byzantine wars)

Saturday, September 1, 2018

Battle of Tryavna Pass (1190 AD)


Eastern Roman Varangian Guard
A Hungarian reenactor's armor and comments
.
"The kit is mainly based on the Alexiad, most notably on the comments of Anna Komnena about the Varangian Guard. This character is of Scandinavian origin, in service of the Byzantine army, rather than the eastern rus contingent of 6000 warriors who formed the core of the Guard later in 988, if I recall correctly. Therefore I based most of the armour and clothing on the Gjermundbu, Birka and Valsgärde finds, with exception of the leather vest. It has a debated origin that byzantine troops used this type of vests along scale and lamellar armour. I refrained to acquire a lamellar armor as the Wisby find turned out to be a "hoax", well not a hoax, only it was originated centuries later. I also looked up on a large number of byzantine manuscripts about guardsmen, but they weren't really helpful aside from the clothing.
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The kit is still incomplete, as I still miss a shield, a proper shoes (will be also based on Birka) and an authentic belt, but I'll have them as well soon enough..
A limb guards were based on the first misinterpreted Valsgärde find, it's not a complicated design, as you can see..
The gloves, well, those are of course a hoax as we don't have a find or manuscritp up to date about protective gloves from this era. But I'm not too keen to lose a finger or two, or my hand entirely, so I gotta wear something. Yeah, I too think the pale leather stands out, and I'm about to dye it darker if I'll have the time and proper materials for it.
(deviantart)

Bulgaria vs Constantinople


Origins of the War

Since 680 AD the Eastern Roman Empire had faced and endless wave of invasions by Bulgarian tribes. At his point that make 510 years of wars, sieges, invasions, counter invasions and slaughter.

In 1190, on paper at least, the Eastern Empire "ruled" from the Danube down to Greece. But huge areas had been re-populated with less than loyal barbarian tribes and had been burned over producing modest to little tax income for Constantinople.

In 1185 we saw the Uprising of Asen and Peter the theme of Paristrion.  

Eastern Roman Emperor Isaac II Angelus, in order to raise money for his wedding with the daughter of King Béla III of Hungary, levied a new tax which fell heavily on the population of the Haemus Mountains. They sent two leaders (Peter and Asen) to negotiate with the emperor. They asked to be added to the roll of the Byzantine army and to be granted land near Haemus to provide the monetary income needed to pay the tax. This was refused, and Peter and Asen were treated roughly. Their response was to threaten revolt.

In the spring of 1187, Isaac attacked the fortress of Lovech, but failed to capture it after a three-month siege. The lands between the Haemus and the Danube were now lost for the Byzantine Empire, leading to the signing of a truce, thus de facto recognising the rule of the Asen and Peter over the territory, leading to the creation of the Second Bulgarian Empire.

The Tarnovo Campaign
 The Bulgarian Army is in red and Byzantines in blue.
.
The Emperor marched the Roman Army north along the coast while the Roman fleet held his right flank just off the coast.
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 The Byzantines made a bluff indicating that they would pass near the sea by Pomorie, but instead headed west and passed through the Rishki Pass to Preslav. The Byzantine army next marched westwards to besiege the capital at Tarnovo. At the same time, the Byzantine fleet reached the Danube in order to bar the way of Cuman auxiliaries from the northern Bulgarian territories.

Medieval Tarnovo
On high ground and surrounded by the Yantra River the Bulgarian capital of Tarnovo was an almost impossible military objective for the Byzantines.

The Tarnovo Fortress
Who thought this was a good idea?
hhh
The Roman Emperor Isaac II Angelos marches deep into enemy territory to attack the Bulgarian capital that is surrounded by the Yantra River.  To capture the city Roman troops would have to cross the river and attack up hill to reach the Bulgarian fortifications.

The newly restored Trapesitsa Fortress in Bulgaria's Veliko Tarnovo is now open for tourists.

Forces Involved

Because of the lack of property histories once again we have next to zero real knowledge of the forces involved in this battle and the massive amount of details about the combat that took place.

Bulgarian Army

The core of the Bulgarian army was the heavy cavalry, which consisted of 12,000–30,000 heavily armed riders. At its height in the 9th and 10th centuries, it was one of the most formidable military forces in Europe and was feared by its enemies. There are several documented cases of Byzantine commanders abandoning an invasion because of a reluctance to confront the Bulgarian army on its home territory.

Bulgarian army used large numbers of Cuman cavalry which numbered between 10,000 and 30,000 riders, depending on the campaign. These were drawn from among the Cumans who inhabited Wallachia and Moldavia.

In the battle of Kleidion the Bulgarian army numbered around 20,000 soldiers. According some estimates the total number of the army including the squads of local militia reached a maximum level of 45,000.

To put it mildly, any Roman Emperor who invaded Bulgaria did so at his own risk. The Bulgarians would have the advantage of defending their own lands and fortified cities while their armies would be easily supported by local militias or allied forces from across the Danube.

I would make an educated guess the number of 30,000 Bulgarian soldiers (perhaps more) defending their country in this campaign. Add to that number thousands of allied Cuman cavalry attacking the Byzantines in the rear.

Eastern Roman Army Strength

The Roman Army

We have a little better idea of the size of the Eastern Roman Army.  In this period it is was roughly 50,000 men under arms.

These professional Tagmata troops would have been divided into assorted units. 

For example, the most famous of all tagmatic units, the 6,000-strong mercenary Varangian Guard, was established ca. 988 by Emperor Basil II (r. 976–1025).  There was the heavy cataphract corps called the Athanatoi (Ἀθάνατοι, the "Immortals") after the old Persian unit, which were revived in the late 11th century by Michael VII Doukas (r. 1071–1078). There were the Megathymoi of the 1040s or the Archontopoulai and Vestiaritai (Imperial Guard) of Alexios I.

The Emperor had these professional units to all upon for an invasion of Bulgaria. What units he selected or the total strength of the army we have no idea.

Using a 50,000 man army as a base number we need to subtract from there. Thousands of troops would have been needed to face the Muslim Turks in Asia Minor. Fortresses would need to be manned and standing mobile forces would be needed to defend the frontier.

Even more troops would be needed to protect Constantinople, the Greek islands, Greece itself and other Western Balkan outposts against Bulgarian invasion.

That 50,000 man army starts shrinking fast.

What we do have is the Emperor himself invading deep into Bulgaria. That means all available troops would be gathered under his command to protect the head of state. We can assume this was an all out campaign by the Byzantine State to crush the revived Bulgarian Empire.

If 30,000 troops are held in place to defend different frontiers that might give the Emperor a force of 20,000 men to invade Bulgaria.  Might give him . . . this is just an educated guess. His army could have been smaller.

The Bulgarians may have had an army of 30,000 waiting for the Emperor and another 10,000 or more Cuman allied cavalry.  That makes a 20,000 man invading Byzantine army look like fresh meat for a Bulgarian grinder.

Late medieval Bulgarian soldier
(pinterest)

Invasion and Siege

In the late autumn of 1186, the Byzantine army marched northwards through Sredets (Sofia). The campaign was planned to surprise the Bulgarians. However, the harsh weather conditions and the early winter postponed the Byzantines and their army had to stay in Sredets during the whole winter.
In the spring on the following year, the campaign was resumed but the element of surprise was gone and the Bulgarians had taken measures to bar the way to their capital Tarnovo. Instead the Byzantines besieged the strong fortress of Lovech. The siege lasted for three month and was a complete failure.
Then the Byzantines dodged a bullet.  The soldiers of the Third Crusade with an army of 12,000–15,000 men, including 4,000 knights reached the Bulgarian lands. Asen and Peter offered to help the Emperor of the Holy Roman EmpireFrederick I Barbarosa, with a force of 40,000 against the Byzantines. But the Byzantines and Crusaders worked out their differences avoiding a major problem.

Emperor Isaac II wanted to end this Bulgarian threat once and for all and planned out a fairly good campaign using both the army and the navy. The problem was he lacked enough troops to pull it off.

The Byzantines marched north from Constantinople and made a bluff indicating that they would pass near the coastal city of Pomorie, but instead they headed west and passed through the Rishki Pass to Preslav.

As the Byzantine army moved inland to the west the Byzantine fleet sailed on to the Danube in order to bar the way of Cuman auxiliaries from the northern Bulgarian territories.  The fleet alone might not have been enough to stop the Cuman cavalry. We can speculate the navy might have had a certain amount of infantry or cavalry with them to secure crossing points on the Danube.

The Byzantines managed to overcome the passes of the Balkan mountains and march on to the Bulgarian capital of Tarnovo.

The Byzantine siege of Tarnovo was unsuccessful. The city was well situated on higher ground and protected by the Yantra River (see photo above). The defense of the city was led by Asen himself and the morale of his troops was very high. They were behind solid walls and defending their nation and people.

The Byzantine morale, on the other hand, was quite low for several reasons: the lack of any military success, heavy casualties and particularly the fact that the soldiers' pay was in arrears.

Asen sent an agent in the guise of a deserter to the Byzantine camp. The man told Isaac II that, despite the efforts of the Byzantine navy, an enormous Cuman army had passed the river Danube and was heading towards Tarnovo to relive the siege. 

Rather than verify the Cuman movements with scouts and his his navy the Byzantine Emperor panicked and immediately called for a retreat through the nearest pass.



Battle of Tryavna Pass

From the frying pan into the fire.

The Byzantine Emperor's plan was bold. Have the navy on the Danube hold enemy reinforcements at bay while the army marched deep into central Bulgaria to capture their capital.  But bold as that plan was the idea of marching a smaller Byzantine army into Bulgaria to attack a powerful fortification while being surrounded by enemy forces was rather stupid and reckless.

Now add into the mix the panic of the Emperor when he was told by one planted soldier that the Cuman cavalry had crossed the Danube. Isaac II did not bother to confirm this single report. He simply decided to turn tale and run for home.

The Bulgarian Emperor deduced that his opponent would go through the Tryavna Pass in his attempt to get to Byzantine territory.

The Byzantine army slowly marched southwards, their troops and baggage train stretching for kilometers. The Bulgarians reached the pass before them and staged an ambush from the heights of a narrow gorge.

The Byzantine vanguard concentrated their attack on the center where the Bulgarian leaders were positioned, but once the two main forces met and hand-to-hand combat ensued, the Bulgarians stationed on the heights showered the Byzantine force below with rocks and arrows.

In panic, the Byzantines broke up and began a disorganized retreat, prompting a Bulgarian charge, which slaughtered everyone on their way.

Isaac II barely escaped; his guards had to cut a path through their own soldiers, enabling their commander's flight from the rout. The Byzantine historian Niketas Choniates wrote that only Isaac Angelos escaped and most of the others perished.

The battle was a major catastrophe for the Byzantines.

The Bulgarians captured the imperial treasure including the golden helmet of the Byzantine Emperors, the crown and the Imperial Cross which was considered the most valuable possession of the Byzantine rulers - a solid gold reliquary containing a piece of the Holy Cross. It was thrown in the river by a Byzantine cleric but was recovered by the Bulgarians. These trophies later became the pride of the Bulgarian Treasure and were carried around the capital, Tarnovo, during official occasions.

11th Century Eastern Roman military formation
(kismeta.com)

Aftermath

Bulgaria was permanently lost to the Eastern Empire.  Tryavna Pass was but one of an endless stream of Bulgarian victories.

Up to that moment, the official Emperor was Peter IV, but, after the major successes of his younger brother, he was proclaimed Emperor later that year. Officially, Peter preserved his title and ruled from Preslav, but the state now governed by Ivan Asen I. In the next two years, he liberated many lands to the west and south-west including Sofia and Niš.

His troops looted Thrace and the Byzantines were powerless to resist the Bulgarian attacks.


 Eastern Roman infantry known as scutatii (Meaning ″shield men″) or skutatoi (on right).

The Empire before Bulgaria broke away.


(Medieval Bulgarian army)      (Second Bulgarian Empire)      (Tagmata)

(Third Crusade)      (Asen and Peter)      (Tryavna)       (pinterest)

(pinterest)      (Byzantine army)