Byzantine Empire, Leo V the Armenian and Constantine, 25 December 813 - 25 December 820 A.D.
BZ99512. Bronze 3 assaria, Anastasi 497, DOC III-1 19, Morrisson BnF 30/Sy/AE/01, Wroth BMC 22, Tolstoi 22, Ratto 1803, SBCV 1635, Sommer 29.7, gVF, well centered on an oval flan, light marks and porosity, 3.886g, 22.4mm, 180o, Syracuse mint, facing busts of Leo, on left, with short beard and Constantine, each wears crown and chlamys, cross between above; reverse Λ•K (initials of Leon and Konstantine), cross above
In 815, Leo concluded a 30-year peace treaty with Khan Omurtag of Bulgaria. The treaty was honored by both sides and renewed after the accession of Michael II in 820. In 821, Thomas the Slav rebelled and laid siege to Constantinople to seize the Imperial throne. Omurtag sent an army to help Michael II put down the rebellion. Byzantine accounts report that Thomas' army was routed at the Battle of Kedouktos (winter 822 or spring 823), however, modern scholars consider the battle a victory, albeit costly, for the rebel.