Battle of Ongal

The foundation of the First Bulgarian Empire. The army of Asparukh is in red. The army of Constantine IV is in blue.

Date	Summer, 680
Location	The Ongal area probably in Danube delta (present-day Tulcea County, Romania)
Result	Decisive Bulgar victory, formation of Bulgaria

Belligerents

Bulgars

Byzantine Empire

Commanders and leaders

Asparukh

Constantine IV

Strength

unknown

"all the themata"50,000

Casualties and losses

Light

Almost the whole army

The Battle of Ongal took place in the summer of 680 in the Ongal area, an unspecified location in around the Danube delta near the Peuce Island, present-day Tulcea County, Romania. The battle had an enormous significance and influence not only for Balkan but also for European history with the creation of the First Bulgarian Empire.

In 632, Khan Kubrat united the Bulgars into the state of Old Great Bulgaria in Patria Onoguria along the coasts of the Black Sea and Caspian Sea. After his death in the 660s his sons divided his kingdom amongst themselves. Batbayan, the eldest son, inherited the throne in Poltava but was defeated by and submitted to the rule of his ambitious relative Cozarig (Kotrag) who had undermined the state's unity by leading his Don-Volga Khazars (Kutrigs) in expansion campaigns extending his empire to the north where Volga Bulgaria would eventually remain. The third and fourth sons Isperih and Kuber marched westward and settled in the Ongal area on the eastern banks of the Danube, Kuber evicting the Avars north into the Carpathians. Eventually the Avars fought back and after Isperih consolidated his rule they launched an attack against the Byzantine lands to the south.

During that time Byzantium was at war with the Arabs who had recently besieged the capital Constantinople. However, in 680 the Byzantines defeated the Arabs and concluded a peace treaty. After this success the emperor Constantine IV was free to move against the Bulgars and led an army against Isperih. In the meantime the Bulgarian leader made an alliance with the Seven Slavic tribes for mutual protection against the Byzantines and formed a federation.

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