Byzantine Empire under the Nikephorian dynasty

During this era Byzantium was almost continually at war on two frontiers which drained its resources, and like many of his predecessors, Nikephoros (802–811) himself died while campaigning against the Bulgars to the north. Furthermore, Byzantium's influence continued to wane in the west with the crowning of Charlemagne (800–814) as Holy Roman emperor by Pope Leo III at Old St. Peter's Basilica in Rome in the year 800 and the establishment of a new empire in Western Europe laying claim to the universal Roman monarchy.

Nikephoros I, 802–811

Nikephoros I had been the empire's finance minister and on Irene's deposition immediately embarked on a series of fiscal reforms. His administrative reforms included re-organisation of the themata. He survived a civil war in 803 and, like most of the Byzantine emperors, found himself at war on three fronts. He suffered a major defeat at the Battle of Krasos in Phrygia in 805 and died on a campaign against the Bulgars.