The First Bulgarian Empire () was a medieval Bulgar-Slavic and later Bulgarian state that existed in Southeastern Europe between the 7th and 11th centuries AD. It was founded in 680–681 after part of the Bulgars, led by Asparuh, moved south to the northeastern Balkans. There they secured Byzantine recognition of their right to settle south of the Danube by defeatingpossibly with the help of local South Slavic tribesthe Byzantine army led by Constantine IV. During the 9th and 10th century, Bulgaria at the height of its power spread from the Danube Bend to the Black Sea and from the Dnieper River to the Adriatic Sea and became an important power in the region competing with the Byzantine Empire. It became the foremost cultural and spiritual centre of south Slavic Europe throughout most of the Middle Ages.