first bulgarian empire - Establishment of the Bulgarian state
There are two different dates for the year of establishment of present-day Bulgaria, based upon two different interpretations of history.

Yet another Bulgar tribe, led by Khan Asparuh, moved westward, occupying today’s southern Bessarabia. After a successful war with Byzantium in AD 680, Asparuh’s khanate conquered Moesia and Dobrudja and was recognised as an independent state under the subsequent treaty signed with the Byzantine Empire in AD 681. The same year is usually regarded as the year of the establishment of present-day Bulgaria.

Another theory is that Great Bulgaria, although it suffered a major territory loss from the Khazars, managed to defeat them in the early 670s. Khan Asparuh, the successor of Khan Kubrat, conquered Moesia and Dobrudja after the war with the Byzantine Empire in AD 680. This war ended with a peace treaty in 681. Therefore, according to some researchers, the year of establishment of present-day Bulgaria has to be considered 632, and not AD 681.

• • first bulgarian empire - Establishment of the Bulgarian state - Establishing a firm foothold in the Balkans
    • After the decisive victory at Ongala in 680 the armies of the Bulgars and Slavs advanced to the south of the Balkan mountains, defeating again the Byzantines and in the next year they were forced to sign a humiliating peace treaty which acknowledged the establishment of a new state in the borders of the Empire. They were also to pay an annual tribute to Bulgaria. In the same time the war with the Khazars to the east continued and in 700 Asparough perished in battle with them. The Bulgars lost the territories to the east of the Dnester river but managed to hold the lands to the west.
  • first bulgarian empire - Establishment of the Bulgarian state - Internal instability and struggle for survival
    • In 753 died Khan Sevar who was the last scion of the Dulo clan. With his death the Khanate fell into a long political crisis during which the young country was on the verge of destruction. For just 15 years ruled 7 Khans who were all murdered. There were two main fractions; some nobles wanted uncompromising war against the Byzantines while others searched for a peaceful settlement of the conflict. That instability was used by the Byzantine Emperor Constantine V (745-775) who launched nine major campaigns aiming at the elimination of Bulgaria. In 763 he defeated the Bulgarian Khan Telets at Anchialus but the Byzantines were unable to advance further north. In 775 Khan Telerig, by tricking Constantine to reveal those loyal to him in the Bulgarian Court, executed all the Byzantine spies in the capital Pliska. Under his successor Kardam, the war took a favourable turn after the great victory in the battle of Marcelae in 792. The Byzantines were thoroughly defeated and forced once again to pay tribute to the Khans. As a result of the victory, the crisis was finally overwhelmed and Bulgaria enterred the new century stable, stronfer and consolidated.