Leo IV the Khazar was Byzantine Emperor reigning from 776 to 780 AD. His sovereignty marked a transition between the period of Iconoclasm and the restoration of the icons.
Leo IV was born in 750 AD, to Emperor Constantine V and his first wife, Empress Tzitzak. Because his mother was a Khazar, Leo was given the epithet 'the Khazar'. He became Emperor at the death of his father while campaigning against the Bulgarian Empire. Leo launched an invasion against Abbasids in 778, invading Syria.
Leo died on 8 September 780, of tuberculosis. During the reign, he issued various coins in the denomination of Solidus, Miliaression, and Follis. These coins were struck at Constantinople and Syracuse mint. Here is a glimpse of Illustration of Leo IV (left) and his son Constantine VI (right), based upon Byzantine coins minted bearing their images.
Image Source: Heritage Auctions