First Bulgarian empire

The First Bulgarian Empire was a medieval state established in the Balkans in the 7th century CE. Founded by Asparukh, a leader of the Bulgars, it emerged in the region between the Danube and Balkan Mountains, a territory nominally under Byzantine control and inhabited by Vlachs and Slavs. The empire was officially recognized by the Byzantine Empire in 681 CE.12

Initially, the Bulgars maintained distinct settlements from the Slavs, accepting tribute from them. However, over time, the Bulgar population was assimilated by the Slavic majority, a process facilitated by the spread of Christianity. Boris I's conversion to Christianity in 864 CE, and the subsequent development of the Old Church Slavonic language and liturgy, played a crucial role in unifying Bulgars and Slavs into a common Bulgarian people. The reign of Simeon I (893–927 CE) marked the empire's zenith, with significant cultural and territorial expansion, though it ultimately led to exhaustion. The empire eventually fell to the Byzantine Empire in 1018 CE.123