General Notes

http://64.1911encyclopedia.org/L/LE/LEO_EMPERORS_.htm    
LEO V., surnamed THE ARMENIAN, emperor of the East, 813-820, was a
distinguished general of Nicephorus I. and Michael I. After rendering
good service on behalf of the latter in a war with the Arabs (812), he
was summoned in 813 to co-operate in a campaign against the Bulgarians.
Taking advantage of the disaffection prevalent among the troops, he left
Michael in the lurch at the battle of Adrianople and subsequently led a
successful revolution against him. Leo justified his usurpation by
repeatedly defeating the Bulgarians who had been contemplating the siege
of Constantinople (814-817). By his vigorous measures of repression
against the Paulicians and image-worshippers he roused considerable
opposition, and after a conspiracy under his friend Michael Psellus had
been foiled by the imprisonment of its leader, he was assassinated in the
palace chapel on Christmas Eve, 820.