A Persian-Roman Army Fights Muslim Invaders

A 19th century Bedouin warrior
The Arab forces facing the Romans would look much like this soldier.
(vikingsword.com)

Battle for the Middle East, Part II
The Coming of Islam

Where is the great historian Procopius when you need him?

We see an amazing lack of information about the final great Roman-Persian War (602 - 628 AD) and the start of the Muslim Arab invasion of the Empire in 629. Because we lack so many details it falls on historians to put their own spin on events. So here I am doing the best an amatuer military historian can do.

The Roman Emperor Heraclius and Persian Shah Khosrau II were is a 26 year long Death Grip of a war that looked like it might never end. But all wars do end. In this case it was with Heraclius at the head of a Roman army marching deep into the Persian Empire and crushing their forces at the Battle of Ninevah.

The Persian War ended in 628 just in time for the first Muslim invasion in 629.

Anarchy in Persia

Shah Khosrau was overthrown and executed by his own son in 627 and peace concluded in 628.

The Persians surrendered the captured lands of Egypt, Syria, Mesopotamia and parts of Anatolia to Rome. The undefeated Persian armies were withdrawn to the homeland.

Over the next four years Persia was in anarchy with ten kings and queens. The final Shah, Yazdegerd III, was thought to be a child of 8 years old upon assuming the throne.

The Persian Empire that faced the invading Arab Muslim armies was bankrupted from the long war, militarily exhausted, had Roman troops still in their country and was in political anarchy.

Shah Khosrau II submitting to Emperor Heraclius

Rome is Supreme

The Roman Empire had decisively won the war and was in the stronger position of the two.

In addition to withdrawing their armies the Persians returned the True Cross to Heraclius. In 630 the Emperor entered Jerusalem by its Golden Gate. Shedding all Imperial insignia Heraclius walked in the city with the cross and restored it to the Patriarch.

The Eastern Empire was at the peak of its fame and power.  But victory masked deep problems.

Like Persia the Empire was financially and militarily exhausted.

Jerusalem had suffered grave damage in the siege of 614. Other cities and farmland over a huge area would also have been damaged or destroyed. Roman Christians held captive in Persia were repatriated and resettled.

With the collapse of the Persian government thousands of Persian Christians migrated to Roman territory under armed escort. This created a new mix of cultures in Roman cities.

Heraclius left Jerusalem and went to the Roman province of Mesopotamia. There he supervised the exit of Persian troops from Roman territory, the return of hostages and the movement of refugees.

A great danger was Heraclius had little time to reestablish governmental rule from Constantinople of the liberated areas. For years provinces like Egypt and Palaestina Prima were ruled from Persia. A Roman Emperor had become but a distant memory. Now the Emperor was back with his tax collectors and attempts to dictate how local Christians were allowed to worship.

Roman-Byzantine reenactor infantryman from the age Justinian. 
The Roman infantry facing the Arabs 100 years later
might have looked much like this soldier. 

The Winds of War

In the year 628 Mohammad dispatched messages to the Shah of Persia, the Roman Emperor, the Governor of Egypt and the Prince of Abyssinia asking them to accept Islam.

In 629 a number of minor raids and expeditions were sent out from Arabia.  Some were defeated and others returned with booty.  In September, 629 a more important expedition was organized resulting the Battle of Mota (Mu'tah).  Some 10,000 Roman troops gave the invading Muslim army a bloody nose forcing them to retreat to Arabia.

Then in 632 Saint Maximos the Confessor wrote a contemporary reference to the barbarian ravages on the frontier that must have been about the Arabs:

"What more unfortunate circumstances could there be here than these 

that hold the inhabited world in their grip? . . .  What could be more 

lamentable and more terrible to those upon whom them fell?  To see 

how a people, coming from the desert and barbaric, run through the 

land that is not theirs, as if it were their own; how they, who seem 

only to have simple human features, lay waste our sweet and 

organized country with their wild untamed beasts."

Heraclius, Emperor of Byzntium - Walker Kaegi (pg 218)

When the Muslim invasion began in 633 it was Persia, not Rome, that was the target.

The Romans had beaten back the Muslims at the Battle of Mota. With anarchy in Persia the Muslims no doubt felt it was a softer target.

Eastern Roman Armored Cavalry
A possible look for the Roman cavalry. The standard stirrup and saddle were both used by the Byzantine Cataphract, allowing for more powerful lance attacks and making it a bit harder to knock him off his saddle. Reflecting the nature of heavy cavalry, the horse was covered in Lamellar armor that extended down to its knees, giving the horse protection for when charges were made against dense formation. It's head was enveloped in a plate headpiece. From front to back, there was not a place above the knees left uncovered.
(necromoprhvsfellowship) 

The Roman Army

The historian Warren Treadgold says there were about 109,000 Roman troops in the field in this period.

This number sounds large but is deceptive. The Empire was enormous ranging from the Pillars of Hercules to Italy, the Balkans, Egypt and Mesopotamia. Troops were required everywhere to man fortresses and drive off invaders. The number of troops available to act as actual field armies was a small fraction of the total.

The mix of the available troops is not available to us. How many are infantry? Cavalry? or militia?

We do know that soldiers were in very short supply. Huge numbers of troops were needed to reoccupy the provinces abandoned by the retreating Persian armies. To fill that gap and to counter the Muslims, Heracilus unsuccessfully tried to shift Roman troops from Numidia in North Africa to Egypt which had a minimal garrison.

Another factor in troop shortages, it appears some level of Roman troops were still inside Persia. They were there perhaps because of the internal political anarchy or to "supervise" the peace of a defeated enemy. In any case those troops were not immediately available to face the Muslims on the frontier of Palestine.

Because of the devastation of war tax money was not coming in. So as a "bonus" the Emperor was cutting expenses left and right and the army was not spared. Even Rome's ally the Arab Ghassanid tribe that protected the desert frontiers of Arabia had their funds cut off at the exact time an invasion from Arabia took place.

Rome needed time and peace to rebuild. Neither were available.

The Arab Army

In 632 AD the Muslim army numbered perhaps 13,000 men.

Because of poverty in Arabia and an arid climate, of that 13,000 perhaps 20% was cavalry.  Infantry would have been an untrained tribal mass.

I do not downgrade the power of tribal based warfare. You can ask the few survivors of the Battle of Teutoburg Forest about tribal warriors. An infantry force of 5,000 fanatical Jihadis slamming into your front lines would have frightened the hardest and most experienced of veteran troops.

But to me the true Arab secret weapon was Islamic Blitzkreig.

In warfare terms think Heinz Guderian and Erwin Rommel.  Like the Allied forces from 1939 to 1942 the Roman Army was a traditional slower moving force with lots of equipment, supplies and camp followers.

The German armored units often avoided combat and plunged deep behind enemy lines to attack the enemy in the flank or the rear. Like the Germans the light Arab cavalry units under their brilliant commander Khalid ibn Walid moved like lightening through the harsh, waterless deserts. The Arab cavalry played that same role as the German armor by rapidly covering hundreds of miles from front to front appearing seemingly out of nowhere to attack Roman troops.

Click to enlarge

Map details the route of Khalid ibn Walid's conquest of
the western portion of the Persian Empire.

The Battle of Firaz

Persians, Romans and Christian Arabs

combine to stop Islam

The Roman crushing of the Persian Empire made that country an obvious first target for Muslim invaders.

From the Muslim point of view it was also critical to prevent Byzantine military recruiting among the Armenians and the other peoples of the Caucasus region. Troops from the Caucasus had form a major part of Heracilus' army that invaded Persia. The conquest of Persian Mesopotamia was a vital first step before attacking Armenia and thereby deny Heracilus access to new soldiers.

The Muslims gathered their army, such as it was. Lt. General Glubb Pasha estimates that the Muslim commander Khalid ibn al-Walid had at best 3,500 warriors available to him. More troops may have come from Arabia as time went on. The Persian forces facing Khalid consisted of local Arab tribes and regular army.

Glubb Pasha explains the situations very well:

"The key to all the early operations, against Persia and against 

Syria alike, is that the Persians and Byzantines could not move 

in the desert, being mounted on horses. The Muslims were like 

a sea-power, cruising off shore in their ships, whereas the 

Persians and Byzantines alike could only take up positions 

on the shore (that is, the cultivated area) unable to launch 

out to 'sea' and engage the enemy in his own element."

Terrorism as a weapon.  After an early victory the ruthless Khalid ordered that all enemy prisoners be beheaded. Arab historians claim that thousands were butchered over a three day period.

In battle after battle Khalid marched up the Euphrates River through Persian Mesopotamia finally coming within 100 miles of the Roman frontier at Firaz.

Firaz was at the outermost edge of the Persian Empire but it still contained an undefeated Persian garrison. There was also a nearby Roman garrison supported by their Christian Arab allies.

The Persians, Romans and Christian Arabs joined forces to face the threat of Khalid.

The Persian-Roman allied army put their backs against 
the Euphrates River to face the Muslims.

Khalid was more or less the master of the Euphrates Valley, but he feared if this undefeated combined force was left alone there could be a Persian re-invasion to take back lost territory.

In December, 633 Khalid marched with a force to the Firaz area and in January, 634 engaged in battle.

There are no records of the size of the forces involved. As commander we can assume Khalid would not have gone into battle with less than several thousand troops. The combined Persian-Roman army might have been the same or maybe smaller. The allies certainly would not have marched to open battle with a tiny force. That would have been suicide. So perhaps their army also numbered in the thousands. It is all guess work.

The combined Persian-Roman army put their backs to the Euphrates River and await the Muslim advance. A bridge over the river was at their rear for an escape if needed.

As usual information is maddeningly vague. It appears Khalid engaged the allies with his infantry. As the front ranks of both sides were engaged in battle he sent his cavalry in a swift lightning movement to engage the flanks of the allies. The Muslims then made a dash for the bridge and cut off the retreat of the allies.

The allies were caught in a double envelopment.

Casualties? We have no idea. We do know that Arab historians do not boast of the allied army surrendering or mass conversions to Islam at sword point. We have to assume the allied army was completely destroyed.

Khalid could now turn his attention on Roman Palestine.

Islamic conquest of Persia

Emperor Flavius Heraclius Augustus
The Emperor was at war for about 27 out of 
his 30 years on the throne.

Sassanid Persian Armored Cataphract

Map of the Middle East on the eve of the Muslim invasions.

(Bagot Glubb)      (Heraclius)      (Persia)      (Firaz)      (Rashidun)

(Byzantine Army)      (Levant)