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

Wednesday, April 12, 2017

The Byzantine Testudo and Shield Wall

EDITOR  -  Eastern Roman military history had suffered from a near total lack of proper histories written by those who witnessed the events.  We historians have to fill in the lack of detailed information with what we know from similar events. In this case I can say that the Byzantine infantry units have not been given proper credit by historians.

Byzantine infantry have lived in the shadow of the Roman Legions. But the Byzantine Army stood centuries longer than the legions of Rome. They must have been doing something right.

The Internet gives us some help.

In 2014 I found a wonderful 1988 Internet article on the Byzantine Infantry Square.  I also found a 1999 article on Byzantine heavy artillery.

Below is a 2004 article on the Roman/Byzantine Testudo formation.  In copying much of the Greek lettering is lost.

When you take in all three of these articles at once you begin to see the highly complex nature of the Eastern Roman Army and the high degree of training of officers and soldiers.


The origin and development of Roman and Byzantine military terms have been the subject of numerous monographs, though the absence of an up-to-date comprehensive lexical work leaves many obscurities in this field. This study examines the fulcum or foËlkon, both as a significant Roman tactical development of intrinsic interest and as an exemplum of the historical and linguistic problems posed by Greek, Roman, and Byzantine military vocabulary.

The word foËlkon is first attested in the sixth-century Strategicon of the Emperor Maurice to designate a compact, well-shielded infantry formation reminiscent of both the testudo of earlier Roman warfare and the hoplite phalanx of classical Greece.  Maurice’s technical description of the fulcum permits its identification in contemporary historical narratives as the standard battle formation of the period.

Maurice’s use of a term drawn from military slang previously unattested in Roman sources, together with the superficial resemblance of the fulcum to the “shield-walls” conventionally associated with “Germanic” warfare, has accentuated its apparent novelty and “unRomanness.” 

The term foËlkon first appears in Maurice’s Strategicon, . . . . Writing in the 590s, the author (hereafter “Maurice”) of this comprehensive military treatise combined in deliberately simple Greek earlier written material with a thorough knowledge of the organisation, training, tactics, and everyday routines of the contemporary Roman army

Maurice prescribes principles of cavalry deployment and tactics modeled on the Avar armies of the period, the Strategicon is on the whole a “codification” or restatement of existing regulations, commands, and procedures in the form of an official “handbook” for officers.

Emperor Maurice (reign 582 - 602).  Painting by Emilian

Maurice chose to write in a plain vernacular, sacrificing stylistic concerns to practical utility, “to which end, we have also frequently employed Latin and other terms which have been in common military use” . . . . the Strategicon is primarily concerned with day-to-day routines and often mundane technicalities, and is aimed at the middle-ranking field officers of the East Roman army, whose literacy is assumed throughout.

Maurice subsequently outlines in more detail what foÊlkƒ peripate›n involves. Before close-quarters contact with the enemy, about two or three bowshots from the enemy battle line, upon the order “iunge,” the infantry were to close in from both the flanks and rear, a manoeuvre Maurice calls pÊknvsiw or sf¤gjiw. Traditionally pÊknvsiw meant reducing the space allotted to each man in a rank to two cubits (three feet), creating a dense formation in which each man was still able to manoeuvre and employ his weaponry; this conventional “close order” appears to correspond to what Maurice describes. 

During this manoeuvre “the men deployed at the front come together side-by-side until they are shield-boss to shield-boss with one another”, while those in the ranks behind stand “almost glued to one another” . Maurice remarks that the rearguards should shove from behind, if necessary, pushing nervous recruits into formation and maintaining a straight battle line.

Thereafter, just outside the range of enemy missiles, the infantry formed a foËlkon:

  • Emperor Maurice:  "They advance in a fulcum, whenever, as the battle lines are coming close together, both ours and the enemy’s, the archery is about to commence, and those arrayed in the front line are not wearing mail coats or greaves. He [the herald] orders, “a d fulco.” And those arrayed right at the very front mass their shields together until they come shield-boss to shield-boss, completely covering their stomachs almost to their shins. The men standing just behind them, raising their shields and resting them on the shield-bosses of those in front, cover their chests and faces, and in this way they engage."

In operations against enemy infantry, therefore, the foËlkon was a compact formation in which the front two ranks formed a “shield-wall.” Maurice characterises this shield wall as “shield-boss to shield-boss”, which should be understood as a colloquial expression rather than a literal description. 

Although Maurice does not define specific measurements, he nowhere implies that the transition to a foËlkon involved reducing still further the intervals between the files, which after pÊknvsiw were already “shield-boss to shieldboss” at the front and “almost glued together” at the rear. This would in any case have fatally restricted the unit’s ability to manoeuvre and fight, and rendered impossible much of Maurice’s subsequent account of how the attack should develop. 

Each man continued to operate in the traditional “close-order” allotment of roughly three feet, so that the edges of his shield just overlapped those of the men to either side, but he retained sufficient space to advance, throw missiles, and slash to his front with a spatha.

It appears that “advancing in a foËlkon” entailed simply an additional defensive measure by the front two ranks, the pur-pose of which was to protect the front of the formation against missiles as it advanced. This would have been particularly the case when fighting the Persians, whose archery remained a tactical problem throughout the late Roman period. 

Persian Sassanid Cataphract armored horse archer
The Shield Wall at the Battle of Callinicum 
We have first hand information on the use of the Roman shield wall/testuda from the historian Procopius who was at the side of General Belisarius during the fight.
Procopius:  "Then the Romans turned their backs to the river so that no movement to surround them might be executed by the enemy, and as best they could under the circumstances were defending themselves against their assailants. 

And again the battle became fierce, although the two sides were not evenly matched in strength; for foot-soldiers, and a very few of them, were fighting against the whole Persian cavalry. Nevertheless the enemy were not able either to rout them or in any other way to overpower them. For standing shoulder to shoulder they kept themselves constantly massed in a small space, and they formed with their shields a rigid, unyielding barricade, so that they shot at the Persians more conveniently than they were shot at by them. Many a time after giving up, the Persians would advance against them determined to break up and destroy their line, but they always retired again from the assault unsuccessful. For their horses, annoyed by the clashing of the shields, reared up and made confusion for themselves and their riders." 

The internal structure of late Roman infantry units ensured that men in the front ranks would know what to do. The less-experienced troops were positioned in the centre of the formation, sandwiched between the junior officers; the “rearguards” prevented flight and literally shoved men into formation, while the “file-leaders” were regularly issued with additional defensive equipment commensurate with their more exposed position, which in this period might include basic items like corselets, as well as greaves and stronger shields, although Maurice notes that even the file-leaders might lack armour. In this solution to the problem of arranging troops of varied quality, success depended less on individual weapons training, and more on unit cohesion, discipline, and stamina.

Within one bowshot of the enemy line, the Roman light infantry began shooting arrows from the rear at a high trajectory. If the heavy infantry were armed with the leadweighted darts commonly called martiobarbuli or other missiles, the formation halted, while the front ranks, fixing their spears into the ground, showered the enemy with these projectiles. 

Late Roman close-order infantry employed an impressive number and variety of missiles, which allowed them to generate casualties and disruption as the battle lines closed, and gave them some of the capabilities traditionally assigned to light infantry. Maurice’s description lacks some details a modern reader would require, but which might have been obvious to a contemporary; presumably the men in the first rank forming the lower tier of the “shield-wall” did not participate in this missile exchange. If such projectiles were unavailable, then closing with the enemy, those at the front hurled their spears like javelins and drew their spathae to fight hand-to-hand, while “those standing behind them, covering their own heads with their shields”, assisted by throwing their spears overhead. 

This last remark does not mean that the whole formation was covered over in the manner of the classical, shed-like testudo, merely that the rear ranks should take care to shield themselves from enemy missiles falling from a higher trajectory. This expedient relates to the changed dynamics of the fighting after closing with the enemy line. It is probable that at close-quarters with enemy infantry the Roman shield-wall was dismantled, having served its primary function as a protective screen against missiles. Maurice suggests that there was greater danger of casualties among the front ranks during the period of approach than in the subsequent hand-tohand fighting, when they would no longer be a target for enemy projectiles, but those to the rear remained exposed to continuous fire from overhead. 

The foËlkon was difficult to manoeuvre, but afforded protection during the last and most dangerous stage of the advance, while from behind the shieldwall the other ranks of close-order infantry and the light infantry to their rear could maintain a constant shower of projectiles. There would have been a concomitant reduction in the momentum in the attack, which perhaps exposed the infantry formation to a longer barrage, but as with the cavalry tactics Maurice describes elsewhere, speed of attack was sacrificed to the essential consideration of tactical cohesion.

 Late Roman cohort reenactment group

Maurice also describes Roman infantry forming a foËlkon when confronting an enemy cavalry charge, though these different tactical circumstances required certain modifications:

  • Emperor Maurice:  "If the enemy [cavalry], coming within a bow shot, attempts to break or dislodge the phalanx, which is hazardous for them, then the infantry close up in the regular manner. And the first, second, and third man in each file are to form themselves into a foËlkon, that is, one shield upon another, and having thrust their spears straight forward beyond their shields, fix them firmly in the ground, so that those who dare to come close to them will readily be impaled. They also lean their shoulders and put their weight against their shields so that they might easily endure the pressure from those outside. The third man, standing more upright, and the fourth, holding their spears like javelins either stab those coming close or hurl them and draw their swords. And the light infantry with the cavalry [stationed to the rear] shoot arrows."

These orders clearly describe a variation suited to cavalry combat, with advice on how to convert the shield-wall into a physical barrier against horsemen.

Maurice’s description of a foËlkon as an anti-cavalry measure differs in detail from the formation he describes operating against enemy infantry, and again not every aspect of the deployment is immediately clear to the modern reader. Whenever Roman infantry oppose cavalry, Maurice requires the front three ranks “to form themselves into a foËlkon, that is one shield upon another”, or a “shield-wall.” 

It is probable, though nowhere explicitly stated, that in this stationary and strictly defensive tactical context the men were positioned more closely than in the manoeuvrable foËlkon deployed against infantry, perhaps equating to the traditional one cubit (one and a half feet) spacing the classical Tacticians called sunaspismÒw. Such dense, well-shielded formations were essential in generating the collective morale required to stand in the face of charging horsemen. 

Maurice explains that the front three ranks should “fix their spears firmly in the ground”, projecting towards the enemy, though the men of the third rank are later required to thrust or throw their weapons. A clue to how these three ranks were positioned is offered by Maurice’s incidental remark that the men of the third rank are “standing higher” or “more upright”. 

The clear implication is that the first and second ranks are lower, probably kneeling and stooping respectively. Maurice nowhere explicitly states this, but, as previously noted, he makes assumptions about the reader’s knowledge, and it will be demonstrated below that this arrangement is attested in earlier periods. We can therefore envisage that the first rank knelt, while the second rank crouched, resting the rims of their shields on the shield-bosses of the first rank, and both ranks thrust forward their spears, fixing their spear-butts into the ground. The men of the third rank, “standing more upright,” in turn rested the rims of their shields on the shield-bosses of the second rank, and more actively engaged any enemy horsemen who approached. 

Assuming even large infantry shields of around a metre in diameter, a sloping “shield-wall” constructed by the front three ranks would reach a height of just over two metres, this additional height being necessary to counter the more elevated position of a mounted enemy. Maurice writes that the men of the third rank “holding their spears like javelins either stab those coming close or hurl them,” meaning they wield their spears overarm and projecting above the shield-wall, ready to thrust or throw them as opportunities arose. 

This arrangement of the first three ranks explains how the men of the third rank, with spears of about two metres in length, were expected to stab the enemy horsemen—in effect the front three ranks were so close together as to operate as a single fighting line. The men of the fourth rank, at a greater remove and unable to stab the enemy with their spears, participated by throwing their weapons over the heads of the first three ranks whenever a target presented itself, and presumably replaced casualties in the battle line.

When confronted by mounted opponents, sixth-century Roman infantry regularly arrayed in a compact defensive “phalanx” fronted by a “shieldwall” bristling with spears. The Syriac Chronicle of pseudoJoshua Stylites reports that near Constantina in 502 some Roman infantry units, abandoned by their own cavalry and facing large numbers of Persian horsemen, “drew up in battle array, forming what is called a ‘chelone’ or ‘tortoise’, and fought for a long time,” though ultimately unsuccessfully. The word the chronicler uses is a Syriac transliteration of xel≈nh, the standard Greek equivalent to Latin testudo; I shall return below to the relationship between foËlkon and testudo. A clearer and more successful example is the battle of Callinicum in 531. After the defeat and flight of the Roman cavalry, a small force of infantry and dismounted cavalry covered the Roman retreat in a manner strikingly reminiscent of Maurice’s foËlkon:

  • "the infantry, and few of them indeed, were fighting against the whole Persian cavalry. Nevertheless, the enemy could neither rout them nor otherwise overpower them. For constantly massed together shoulder-to-shoulder into a small space, and forming with their shields a very strong barrier, they shot at the Persians more conveniently than they were shot at by them. Frequently withdrawing, the Persians would advance against them so as to break up and destroy their line, but retired again unsuccessful." 

Holding firm in the face of charging cavalry was one of the most psychologically demanding tasks for infantry; not only was late Roman infantry capable of standing up to cavalry attacks but deterring cavalry was actually one of its primary functions. On the sixth-century battlefield infantry retained an important, albeit more passive role, serving principally as a firm bulwark, behind which Roman cavalry, employing highly fluid tactics, could withdraw and regroup if pushed back. Given sufficient training and morale, infantry possessed the potential for greater cohesion and more accurate firepower than cavalry, and when combined with archers and slingers the effects on enemy horsemen could be devastating.

Finally, it is to be noted that even late Roman cavalry, in moments of crisis or simply wherever tactically beneficial, transformed themselves into infantry and also arrayed in a foËlkon. A minor action in Lazica in 550 is instructive, where Roman and allied cavalry, finding themselves suddenly outnumbered by Persian horseman, dismounted and

  • "arrayed themselves on foot in a phalanx as deep as possible, and all stood forming a close front against the enemy and thrusting out their spears against them. And the Persians did not know what to do, for they were unable to charge their opponents, now that they were on foot, nor could they break up the phalanx, because the horses reared up, annoyed by the spear points and the clashing of shields."

There are numerous other late Roman examples of this tactical expedient and it is expressly what the Strategicon enjoins cavalry to do in these circumstances.

The tortoise formation was one of the prime examples
of Roman ingenuity at warfare.


Later Byzantine Development

Other than Maurice, the only author to use the term foËlkon in a late antique context is Theophanes Confessor (writing ca 810–814), in his account of Heraclius’ campaigns against the Persians (622–628), which occurred a generation after the composition of the Strategicon.

Theophanes writes that at the battle of Nineveh in 627 the Persian commander Rhazates “arrayed his forces in three foËlka”. Here Theophanes, who uses the word nowhere else, appears to mean simply a battle line divided into three broad divisions rather than Maurice’s testudo-like infantry formation. Theophanes himself elsewhere reports this tripartite deployment by Persian armies, employing non-technical language to designate the three “divisions”, and he notes that the Roman line was similarly divided into three “phalanxes”; indeed, sixth- and early seventh-century Roman sources indicate that this was a regular practice of Persian armies. Theophanes therefore uses the word foËlkon differently than does Maurice, as simply a generic term for a large body of troops, whether Roman or foreign.

. . . . two works ascribed to the Emperor Leo VI (886–912), the so-called Problemata and Tactica or Tactical Constitutions. The Problemata, the first work Leo composed in this genre, is preserved only in Mediceo-Laurentianus. It takes the form of a “military catechism,” in which the compiler poses questions which he then answers with excerpta from Maurice’s Strategicon . . . .  the Problemata genuinely reflect late ninth-century practice; continued references to Avars and Persians do not inspire confidence in its contemporary utility. For the present it suffices to note that in answer to the question “How do they advance when the archery is about to commence?” the compiler reproduces Maurice’s description of the foËlkon operating against enemy infantry with only very minor changes, though he omits his anticavalry version.

Leo appears not to understand Maurice’s reference to “shield-bosses”, which is almost certainly late Roman terminological usage; the limited evidence suggests that by the tenth century boÊkoulon had come metonymically to mean “shield” in toto. It is possible that Leo’s textual alteration also reflects changes in shield design and construction in the intervening period.

 . . . . . the treatise on guerrilla warfare Per‹ paradrom∞w or De velitatione ascribed to Nicephorus II Phocas (963–969). The author possessed a detailed knowledge of Leo’s Tactica and its tactical precepts. Yet throughout he employs foËlkon to designate a body of troops in formation, apparently infantry or cavalry, but more often the latter, sent out to protect smaller parties engaged in foraging and pillaging, accompanying them into designated localities in the morning, remaining at hand during the day, and escorting them back to camp in the evening. This sense is clear from the often-repeated formula “a foËlkon, whose role is to protect them while they are dispersed for plundering”.

A foËlkon might also be stationed outside the camp to protect grazing horses or livestock. The author mentions foËlka only in the context of invading Arab forces, and his recommendations for surprise attacks on Arab encampments or dispersed raiding parties are premised on the potential presence of such a foËlkon coming to the rescue and how Byzantine troops should counter it. These protective escorts were not unique to Arab tactical arrangements nor Arab in origin, however; the author merely uses a Greek term to describe what was a standard feature of both Arab and Byzantine armies.

(Mid tenth century military documents are nearly identical to those of Maurice.)

Again it is important to appreciate, however, that new terminology is not necessarily indicative of a new phenomenon. In the late sixth century Maurice clearly describes, and in very similar language, identical protective escorts guarding foraging parties:

  • Emperor Maurice:  "When some men go out on a plundering expedition, not all of them are to be occupied in pillaging, but they must be divided into two—those who are engaged in plundering, and the majority who escort them in close formation as their guard, whether the attack is against a country, an enemy entrenchment, a herd of beasts, a baggage train, or any other objective. Do this also when the whole army collectively undertakes a plundering expedition, again so that not all the men are occupied in pillaging, but if an opportunity for foraging supplies should arise, some must engage in foraging, others in close formation must escort them, otherwise, if all the available men were occupied in pillaging or foraging, some surprise attack or ambush would be undertaken by the enemy and our soldiers would not be able to rally themselves."

This type of escort in force, to which Maurice applies no specific terminology, is precisely what mid tenth-century authors designate a foËlkon. In fact this was a standard procedure for Roman armies dating back at least to the early Principate, and the later Byzantine usage merely reflects changes in terminology rather than practice.

Given the difficulties we have seen in the testimony of Leo’s tactical writings, it is impossible to be certain how and when foËlkon came to mean the mounted escorts or patrols attested in mid tenth-century military literature, distinct from the battle formation for infantry described in Maurice’s Strategicon, and the evidence of the intervening period perhaps points to long-term multiple usage, though the underlying concept of a compact body of troops arrayed for combat is consistent.

The variant meanings of foËlkon over this four-hundred-year period therefore correspond to the broad development of late Roman-Byzantine military vocabulary.

Philip Rance
March, 2004

Rome - Testudo Formation

Byzantine 10th century Varangians in shield wall

(www.legioxxirapax.com)      (Maurice)