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The Third Battle of Anchialus
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The Third Battle of Anchialus
By John Patrick Hewson

For close to 500 years the Byzantine Empire conducted relations, sometimes as allies, sometimes at war, with the Bulgars. The Bulgars were originally a Turkic people who, like other Central Asian peoples, had a reputation as military horsemen, and they had developed a strong political organization based on the Khan as leader. The Khans came from the aristocratic class of Boyars, and were augmented by senior military commanders called Tarkhans. In the second century, the Bulgars migrated to an area between the Black Sea and the Caspian Sea, and sometime between 351 and 377, a group of them crossed the Caucasus to settle in Armenia.

Fleeing from the Huns at the beginning of the fifth century, a large number of Bulgars reached an area of fertile land between the Donets and Don valleys and the Sea of Azov. Some settled in this area, founding the state of Black Bulgaria, which became known as Great Bulgaria, and which flourished until destroyed by the Mongols in the thirteenth century. Others moved towards central Europe, settling in the Roman province of Pannonia, and accompanying the Huns in their raids into Europe between 377 and 453, dispersing into southeastern Europe in 453 with the death of Attila. Towards the end of the fifth century, these Bulgars fought the Ostrogoths as Byzantine allies, but from 493 they carried out raids on the western Byzantine outposts. These raids became so serious that they forced Byzantine emperor Anastasius to begin construction of the so-called “long wall” and to undertake the strengthening of the Danubian defensive perimeter. At the end of the sixth century, however, there was civil strife among the Bulgars, as the Kutrigur tribal faction united with the Avars to defeat the Utigurs. At this time Byzantine emperor Maurice incorporated some of the Bulgars as foederati into the Byzantine army, using them for duty in North Africa.

The eastern Bulgars were subjugated by the Gōktűrk Khanate in 568. The Utigur and Kutrigur Bulgars, as well as the Onogurs, a non-Bulgar Turkic tribe, broke loose from Gōktűrk control in 634 under khan Kubrat and formed an independent state known as the Onogundur-Bulgar Empire, situated between the lower course of the Danube in the west, the Black Sea and the Sea of Azov in the south, the Kuban river in the east and the Donets in the north. After the death of Kubrat in 665, this state was broken up by the Kazzars, and one group of Bulgars under Kubrat’s son Batbayan returned to their traditional homelands to the north of the Black Sea. Another group led by his brother Korbus migrated to the Volga and Kama basins in Russia, becoming known as Volga Bulgars. A third group led by Asparukh, a third son of Kubrat, crossed the Danube and occupied southern Bessarabia (modern Moldova), becoming known as Danube Bulgars. After a successful war with the Byzantine Empire, highlighted by the Battle of Ongal in 680, the Danube Bulgar khanate was recognized as a separate state under a treaty with emperor Constantine IV the following year. The Bulgars had captured the Byzantine province of Moesia, which formed the basis for the modern state of Bulgaria, and which at the time was known as White Bulgaria. The treaty recognized Pliska as the capital. This area had a large pre-existing Slavic population, which exerted cultural influence on the Bulgars.

But in 689 Constantine’s son Justinian II defeated the Bulgars and annexed Thesalonika. In 708, the First battle of Anchialus[1] (modern Pomorie, Bulgaria, near Burgos on the Black Sea) took place. The army of the Bulgar khan Tervel, the fourth khan of the Duolo clan, deployed with cavalry on the wings and infantry in the centre. The Bulgar cavalry on the wings spread out to attack the Byzantine cavalry, which had been deployed some distance from their main army. Tervel’s infantry then attacked the Byzantine infantry in the centre. The result, interpreted by some historians as a Byzantine defeat, could be said to be a bloody standoff, as casualties were high on both sides. However, Justinian, plagued by domestic problems, was eager for peace, and a treaty was signed ending hostilities.

But the Bulgars, kept from eastward expansion by the Magyars and from westward expansion by the Franks, once again turned their attention to Byzantium. In 763, Telets, third khan of the Ukil clan, fought the Second battle of Anchialus against the Byzantine army of Constantine V. Telets’s army broke through Byzantine lines and advanced upon Constantinople, but were driven back by the Byzantine troops garrisoned there, during which fighting Telets was killed.

In 811, Byzantine emperor Nikephorus I marched into White Bulgaria and sacked and burned Pliska. While the Byzantine soldiers were occupied with looting the city, troops under khan Krum, who had restored the Duolo clan in 803, entered the Byzantine camp and killed Nikephorus and a number of his commanders. This was followed up two years later when Krum made another assault against Constantinople. However, the Bulgars were defeated by the army of Emperor Leo V and Bulgar military power was broken. Krum died the following year and his son Omurtag signed a peace treaty. Relations then became peaceful, and there is archaeological evidence of commercial contacts between the Bulgars and the Byzantine Empire during this period. The main trading ports were Messembria, (modern Nesebăr) and Develtos (modern Debelt), north and south respectively of Anchialus, as well as Constantinople itself.

In 870 Bulgar khan Boris I turned to Byzantium for support after a letter he had sent to Pope Nicholas I requesting an ecclesiastical reinforcement of Christianity in order to counter the increasing power of the pagan Boyars had not met with success. His other purpose was to increase his own authority as a way of lessening Bulgaria’s dependence upon foreign powers. As a result, a council was held at Constantinople which attached the Bulgar state to the jurisdiction of the Patriarch of the Byzantine church while also providing it with a measure of authority for conducting its own internal affairs. At the same time Byzantine missionaries spread orthodox Christianity, using Pliska as a base. The Bulgar state was also expanded by the annexation of Prespa and Ohrid. In 889 Boris abdicated and went to a monastery. He was succeeded by his eldest son Vladimir. Vladimir sought to convert the Bulgars back to Paganism with the support of the dissident Boyars. Consequently, in 893, Boris went to Pliska, had Vladimir blinded and incarcerated and proclaimed his second son Symeon as the new khan. He also transferred the capital from Pliska to Prreslav. He then returned to the monastery.

Symeon was highly intelligent and in addition to his military talent he was a teacher, sage and lawmaker among his own people. He had a reputation for justice and philanthropy, and he has become known as Symeon the Great because during his rule Bulgaria reached the height of its power and its greatest size. Byzantine authority in the Balkans became limited to Greece, part of Thrace and a strip of land between the Rhodope Mountains and Aegean coast, which included Macedonia. Thesalonika became the second city of the empire, and Dyrrachium (modern Durres, Greece) the third.

Meanwhile at Constantinople, in 886 Leo VI became Byzantine emperor. Symeon wanted three things from Byzantium: advantageous trading relations; tribute; and recognition of his title as Emperor. In a treaty negotiated with Leo upon his accession to power in 893, Symeon gained tribute as well as a grudging recognition of his title and the establishment of trading relations. Leo followed the diplomatic and foreign policies of his Father Basil I, but war broke out with the Bulgars in 894 because of Leo’s unilateral decision to transfer the designated entry port for Bulgar traders from Constantinople to Thesalonika and to impose a customs duty. This had the effect of diverting the lucrative trade route from the Danube to Constantinople and thus away from Bulgar territory. This meant that the Bulgars could no longer increase their wealth by imposing travel duties on merchants.

As a result of what he considered a breach of the 893 treaty, Symeon crossed with an army into Byzantine territory. Leo’s Armenian military advisor (and father of one of his mistresses), Stilianos Zautzas, suggested an alliance with the Magyars. As the Bulgars attacked Leo’s army the Magyars attacked white Bulgaria from the north, and Symeon was forced to negotiate a truce. He then made an alliance with the Pechenegs, known to the Byzantines as Patzinaks, who lived in the Volga basin, to jointly attack the Magyars. After defeating the Magyars, Symeon once more turned his army upon the Byzantines. He defeated Leo at Bulgarophygum in 896 and forced him to conclude a peace treaty under which he was forced to substantially increase the tribute to compensate for lost Bulgar revenue.

But the situation changed drastically when Leo died in 912. In the later years of his life, Leo had set up a Council of Regency to handle the affairs of the empire, including the succession, and they now approved his brother Alexander, who had seized the throne without their consent. Alexander promptly let it be known that he would no longer pay the tribute to Symeon. Symeon moved his army across the Danube into Byzantium and threatened war. Alexander died the following year and a power struggle ensued. Symeon, whose army stood before the walls of Constantinople, did not attack the city. Instead, he bided his time, seeking to gain advantage from the internal strife.

The struggle had its roots in events prior to Leo’s death. Leo had promised Constantine, his five year-old son by his mistress Zoe Karvounopsina[2] in marriage to one of Symeon’s daughters. However, this did not sit well with the Patriarch Nicholas Mystikos, who regarded Constantine as illegitimate. Negotiations took place and Nicholas agreed to recognize Constantine as legitimate provided that Leo and Zoe would separate. However, Leo broke his promise and married Zoe in 906 after Constantine had been baptized. A furious Nicholas withdrew his recognition of Constantine and locked to gates of St. Sophia’s cathedral to Leo, whereupon Leo appealed to Pope Sergius III and Nicholas was deposed as Patriarch. In 908. Leo named Constantine as co-emperor.

When Alexander died Nicholas was able to get himself acknowledged as the head of the Council of Regency. He promptly refused to recognize Constantine as successor and sent him into exile.[3] He also granted Symeon an audience during which he reaffirmed Leo’s marriage promise and personally crowned him as Emperor of Bulgaria. Symeon then returned to Pliska with his army.

This angered Zoe, who staged a coup and, with some popular support, placed herself at the head of the Council of Regency. She called off the marriage promise and refused to recognize Symeon as emperor of Bulgaria, which she regarded as a Byzantine vassal state. Symeon now had neither tribute nor recognition, nor the hope of gaining influence at Constantinople through the marriage. He therefore moved his army back into Byzantine territory, determined to reassert Bulgar independence.[4]

The result was that Nicholas, at the command of Zoe, sent a letter to Symeon accusing him of not being content with the “honor” he had previously received of being considered a vassal prince of a Byzantine vassal state. Symeon once again offered concessions in return for the restoration of tribute and recognition, but Zoe rejected any and all attempts at negotiation. She had made up her mind to invade Bulgaria. She assembled a massive army which marched to Anchialus on August 20, 917, hoping to take Symeon by surprise.

The nucleus of Zoe’s army of approximately 70,000 was the Togma (plural; Togmata), a guards cavalry brigade of four regiments, of which the Scholae were the most senior. Each regiment could vary in size from about 1,500 to 4,000 men and at the time of the battle were very large. Each Togma was commanded by a Domestikos. There were also provincial detachments of Togmata, commanded by a Topoteretei, who was second in rank to a Domestikos. The Empire was divided into military administrative districts called Thema (plural: Themata), and the regular Thematic armies were commanded by a Strategoi, or provincial military governor. The basic tactical unit was the company sized Bandun or Banner (plural: Banda). Infantry Banda consisted of 256 men, subdivided into 16 details or Lochaghiai of 16 men each. Cavalry Banda were about 300 strong, divided into six Allaghia of 50 men each. On the battlefield an infantry Banda was traditionally deployed in 16 files, each being 16 deep. Each file was commanded by a Lochagos or file leader and ended by a Ouragos or file closer. A cavalry Banda was traditionally arrayed in open order, each Allaghia being subdivided into five Deckarchiai of ten men, deployed in two files of five deep, with a Deckarchos or commander in the front rank of each.

The Byzantine heavy infantry wore helmets and chainmail or lamellar vambraces, leather pteruges and padded cloth or leather greaves. They carried large oval shields, spears and a heavy sword. To resist cavalry charges, spearmen and archers were deployed in special formations, and the main role of infantry in battle was to support the cavalry, acting either as a defensive barrier upon which the cavalry could redeploy or as a defensive screen behind which it could hide if pursued. The heavy cavalry wore scale armour for the torso, a face shield, metal or hardened leather vambraces, leather greaves and a helmet. They were armed with heavy lances, swords and small round shields. The horses also wore bardings and chamfrons. Thus equipped, the heavy cavalry was well protected, but the weight of all the protection often resulted in slowing the impetus of the charge and quickly tiring the horses. As a result, heavy cavalry often acted in conjunction with lighter cavalry in co-ordinated movements against enemy infantry or cavalry.

Symeon’s army numbered less than the Byzantines, about 35,000 to 40,000. Its core was the heavy cavalry. At this time, the Bulgars had the finest heavy cavalry in Europe, and it had a reputation for instilling fear into enemies with its ferocious charges on the battlefield. The traditional Commander-in-Chief was the Khan himself, and Symeon accompanied his men into battle, sharing their hardships, which made him very popular and kept morale high. Second in command was the Kavakhan, who assumed the duties of C-in-C when the Khan was absent. The standing army consisted of the Khan’s personal bodyguard of handpicked men, which varied in size, but during times of war almost all the able-bodied men in the kingdom could be levied, separated and recruited by clans. The infantry was recruited primarily from the Slavs. It was lighter armed than the cavalry and was generally commanded by Bulgar officers. On the battlefield the army was deployed in left and right wings and a centre. In general (although there were exceptions) the Bulgar heavy cavalry were on the wings and the Slavic infantry in the centre. There was also a contingent of the traditional light mobile cavalry of the steppe allies, which was usually placed on the flanks. In addition, a contingent of heavy cavalry was hidden on one flank so that it could attack with a devastating charge at an opportune moment in the battle. A cavalry unit was also held in reserve behind the main battle line in order to prevent an attack from the rear in the rare event that an enemy was able to outflank the initial attack. Feigned retreat was used to draw an enemy into a trap and ambush him.

The heavy cavalry wore helmets, either chainmail or plate armour, and the horses were equipped with bardings. Heavy cavalry were armed with a heavy sabre, a long spear and a heavy mace. Light mobile cavalry were equipped with the traditional weapons of horse archers, the bow and the lasso. The Slavic infantry was generally lighter armed, carrying sword, spear and wooden shield. In order to distinguish themselves to their men in the heat of battle, officers wore gold or silver belt buckles as insignia of rank.

In the heavy cavalry, iron discipline prevailed, especially just before a battle, with the slightest imperfection in weaponry, armour, horse or behavior punishable by severe penalties up to and including execution. During peacetime, discipline was not quite so severe, but strict codes of dress, equipment and behavior were still rigidly applied. Among the Slavic infantry discipline on the battlefield was not quite as harsh as among the heavy cavalry, but was rigidly applied. The major reason for this, besides the obvious need for discipline during a battle, was that the Bulgar army was inextricably linked to the state, which depended upon military victory for its survival. As such, the heavy cavalry was considered the backbone of the state, and therefore of immense value. Heavy cavalry horses were considered almost sacred, and were bred for strength, steadiness and agility and treated with special care. The death penalty was applied for mistreatment of a heavy cavalry horse. An addition, the lighter horses required for the horse archers of the light cavalry were bred for speed and were often as highly prized as the heavy cavalry horses.

The battle took place on the western shore of the Black Sea. Symeon deployed his army in two lines with the sea to his left. The first line had heavy cavalry on the wings and Slavic infantry in the centre. The second line consisted of the remaining Slavic infantry in two large phalanxes. Concealed on the right, to the northwest of Anchialus, was a large contingent of heavy cavalry. The Byzantine army facing them had three phalanxes of heavy cavalry in the front line, two phalanxes of infantry in the second and a third phalanx of infantry to the right. However, they were deployed south of Symeon’s forces so that the sea was behind them. The Togma were guarding the Byzantine camp, which was located in the rear between their army and the sea. Leo Phokas was in command of the Byzantine land forces, and a plan had been made for Byzantine admiral Romanus Lekopenus[5] to transport a force of Pecheneg volunteers across the Danube to attack Symeon’s army from behind at the same time as they attacked from the front. However, the inability of Romanus to get along with John Bagos, the Byzantine commander of the Pechenegs, led to them returning to their own lands and Romanus returning to Constantinople, neither commander taking any part in the battle.

The battle opened with Leo Phokas ordering a massive cavalry charge. Three phalanxes of Byzantine heavy cavalry thundered towards the Bulgars. Symeon staged an orderly feigned retreat. This caused the right phalanx of the Byzantine heavy cavalry to turn and pursue them along the coast road. Then a contingent of Symeon’s heavy cavalry turned and attacked the road, spreading out along it so as to block the Byzantine escape routes. At the same time the concealed heavy cavalry on the Bulgar right broke cover and made a devastating charge for the Byzantine camp. Seeing this, the rest of the Byzantine cavalry abandoned pursuit and turned to defend their camp. Symeon had achieved his objective and effectively split the Byzantine forces. The Byzantine right phalanx was driven into the sea and annihilated. The remaining Byzantine cavalry, which had turned in defense of their camp, was forced to spread out along the coast road, pursued by the Bulgars. The Byzantine camp Togma was forced onto a narrow spit of land jutting out into the sea on the right, where it was soon destroyed, with most of its troops being driven into the sea. The Byzantine army was almost annihilated, suffering one of the greatest defeats in early medieval European history. Leo Phokas survived the battle by fleeing to Messembria, but many of the unit commanders, such as Constantine Lipis, who was his chief military advisor, and John Grapson, who commanded the Togmata, were killed. The exact number of Byzantine casualties is not known but is believed to have been at least 50,000 and probably closer to 55,000. Bulgar casualties were probably less than 10,000.

After the battle Symeon advanced as far as Constantinople, during which he inflicted a second defeat on a smaller force raised by Leo in a village in Thrace called Katassurtas by storming the village at night. At Constantinople, the defeat raised a furor. Romanus was held as a scapegoat for it, not having transported the Pechenegs across the Danube nor having deployed the Byzantine navy to rescue the fleeing troops. His execution was only prevented by the intervention of the Patrician Constantine Gongylos with Zoe. Symeon forced Zoe to raise him to the rank of Caesar and he was betrothed to her in marriage. The marriage never took place.

However, Romanus gained control of the Council in 919 and had himself acknowledged as emperor. He deposed Zoe to a convent. At his coronation in 920 he arranged for the marriage of Constantine to his daughter Helena and reiterated the refusal of Symeon’s title. As a result, Symeon remained active in the Balkans, invading Serbia and Greece as far as the Gulf of Corinth. He then retired to Preslav, but not before establishing garrisons at several towns and raiding as far as the outskirts of Constantinople itself.

Romanus exercised careful and clever diplomacy with regard to Symeon, refusing to meet with him in battle while communicating with him from behind the walls of Constantinople. From letters exchanged between Symeon and Nicholas it becomes clear that Nicholas thought the Byzantine attack of 917 had been unjustified. There is also evidence that Symeon was greatly aggrieved by the slaughter. At a meeting between the two in 924, Symeon rode the same horse he had ridden in the battle which still bore the scar of a wound inflicted there.

Romanus grudgingly raised Symeon to the title of Emperor of the Bulgars in 924 at a ceremony outside Constantinople, at which, according to letters by Romanus’s imperial secretary Theodore Baphnopatus, the tribute was reinstated, while Romanus refused any consideration of raising it or considering Symeon’s demand for a powerful position within the Byzantine government. Full peace was not achieved, for Symeon then sought naval support from the Muslims, which Romanus was effectively able to pre-empt by offering the Caliphate more concessions. There was a long and drawn out campaign in the Balkans which Symeon lost in 926 after his defeat in a war with Tomislav of Croatia, whom Romanus reinforced.

Symeon died in 927 and was succeeded by his son Peter, who sought an accommodation with Byzantium. As a result a marriage was arranged with Romanus’s granddaughter Maria with Romanus recognizing the legitimacy of the recently formed Bulgarian patriarchate. Peace with Bulgaria enabled Romanus to turn his attention to the eastern campaign. He was sent into exile in a monastery in 944 by his eldest son Christopher, who had risen in revolt against him. Christopher, whom Romanus Had made Co-emperor in 920, and his other son Stephen, whom he had made Co-emperor a year later, then became engaged in a struggle with Constantine. Constantine emerged victorious and Christopher and Stephen joined their father in the monastery. Thus in 944, after 32 years on the sidelines, Constantine, whom many considered the legitimate successor to his father Leo VI, became emperor as Constantine VII. He assumed the surname Porphyrogenitas, which means “born in the purple (ie Royal) chamber” as a further assertion of his legitimacy.

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[1]. Known as Achelios to the Byzantines.

[2]. Her last name means “with coal black eyes.”

[3]. Constantine would return in 945 as Emperor Constantine VII. He proved to be one of the more competent emperors.

[4]. He had every reason to be optimistic. Bulgarian armies had defeated the Byzantines on several occasions before, such as at Marcelae in 792, at Pliska in 811 and at Versiakia in 813, and neither of the previous two battles of Anchialus had been decisive defeats.

[5]. He would become the future Emperor Romanus I.

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© 2023 John Hewson

Written by John Hewson. If you have questions or comments on this article, please contact John Hewson at:

About the author:
John Hewson was born in England. He holds a BA from UBC and an MA from Carleton in International Relations. He comes from a military family; his father was a staff sergeant in Royal Engineers. He is now retired and worked 23 years for Passport Canada. He has always been interested in military history and has written several brief battle histories. He is mainly interested in military history of ancient times and early middle ages, and also World War I.

* Views expressed by contributors are their own and do not necessarily represent those of
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