Bulgarian-Byzantine War of 755-72

The East Roman Empire is beset from within by Iconoclast controversy and from without by the Arab Caliphate to the east and south and the newly formed Bulgarian Empire to the north.

Constantinople’s successes in the east make it possible to pursue an aggressive policy in the Balkans, where the Bulgarians now dominate Thrace.

With the resettlement of Christian populations from Armenia and Syrian into Thrace, Constantine aims to enhance the prosperity and defense of the area, causing concern to the Empire's northern neighbor, Bulgaria, and leading the two states to clash in 755.

The reign of Kormisosh inaugurates a prolonged period of war with the Empire.

Kormisosh demands the payment of tribute, perhaps constituting an increase in the traditional payments.

Rebuffed, Kormisosh raids into Thrace, reaching the Anastasian Wall stretching between the Black Sea and the Sea of Marmara forty kilometers in front of Constantinople.

Constantine marches out with his army, defeats the Bulgarians and turns them to flight.

Greek-Bulgarian conflict is resolved with a peace treaty between Kormisosh and Constantine V that probably confirms the existing frontier.

It is sometimes supposed that this defeat brought the reign of Kormisosh to its end through a palace coup, but the next ruler Vinekh may have been from the same royal house.

Vinekh ascends the Bulgarian throne after the defeat of his predecessor Kormisosh by the Eastern Roman Emperor Constantine V, which has led some scholars to assume that he was an usurper.

Around 756 Constantine V campaigns against Bulgaria by land and sea, and defeats the Bulgarian army led by Vinekh at Marcellae (Karnobat).

The defeated monarch sues for peace and undertakes to send his own children as hostages.

Constantine V invades Bulgaria again in 759, but this time his enormous army is ambushed in the mountain passes of the Stara Planina (battle of the Rishki Pass) and completely defeated.

The Byzantine historian Theophanes the Confessor wrote that the Bulgarians killed the strategos of Thrace, Leo the commander of Drama, and many soldiers.

Khan Vinekh does not take the favorable opportunity to advance on enemy territory and sues for peace.

This act is very unpopular among the nobles and the Khan will be murdered in 762.

Bulgarian power falters as first one khan is assassinated, then another, followed by the successive elections of two more khans, resulting in a five-year peace with Constantinople.

The Bulgarian Khan Vinekh, after the success in the battle of the Rishki Pass in 759, had showed surprising inaction and desire for peace.

This eventually costs him the throne and his life when, in 762, he is assassinated, together with all his kin.

Telets, a leader of the conspiracy, is elected to succeed him.

According to the Namelist of Bulgarian Rulers, Telets reigned for three years "instead of another", and he was a member of the Ugain clan.

This is corroborated by the Byzantine sources, which indicate that Telets replaced the legitimate rulers of Bulgaria.

The same sources describe Telets as a brave and energetic man in his prime (about thirty years old).

Scholars have conjectured that Telets may have belonged to an anti-Slavic faction of the Bulgarian nobility.

Telets leads a well-trained and well-armed army against the Empire and devastates the Empire's frontier zone, inviting the emperor to a contest of strength.

Emperor Constantine V marched north on June 16, 763, while another army is carried by a fleet of eight hundred ships (each carrying infantry and twelve horsemen) with the intent to create a pincer movement from the north.

Telets at first fortifies the mountain passes with his troops and some twenty thousand Slavic auxiliaries.

Later he changes his mind and leads out his troops to the plain of Anchialos (Pomorie) on June 30.

The bloody battle of Anchialus begins at mid-morning and lasts until dusk.

At the end, Telets is deserted by his Slavic auxiliaries, who desert to the emperor, who wins the field, but chooses to return home in triumph.

According to the Byzantine sources, Constantine V brought home a throng of Bulgarian prisoners in wooden restraints, for the entertainment of Constantinople's populace, then had them killed.

The military defeat had sealed the fate of Telets, who is lynched together with his supporters by his rebellious subjects in 765.

Some scholars think that Sabin, his successor, was omitted from the Namelist of Bulgarian Rulers because he was a Slav, but his name could indicate Latin or even Iranian origins.

He was related by marriage to Kormisosh, who was either a father-in-law or a brother-in-law of Sabin.

Since the relation is by marriage, Sabin would not have actually belonged to the Vokil clan.

Sabin rises to the throne after the murder of Telets in 765 and represents that part of the Bulgarian nobility which is seeking a policy of accommodation with the Empire.

Accordingly, he swiftly dispatches secret emissaries to Emperor Constantine V, seeking to reestablish peace.

When the negotiations are discovered, the Bulgarians rebelled and hold an assembly in which they accuse Sabin of causing Bulgaria's enslavement by the Empire.

Sabin, deserted by his supporters, flees to Mesembria (Nesebăr) in 766, whence he goes to …