In 812 Michael I reopened negotiations with the Franks, and recognized Charlemagne as "imperator" and "basileus" (Emperor), but not Emperor of the Romans. In exchange for that recognition, Venice was returned to the Empire. However, under the influence of Theodore, Michael rejected the peace terms offered by Krum and provoked the capture of Mesembria (Nesebar) by the Bulgarians. After an initial success in spring 813, Michael's army prepared for a major engagement at Versinikia near Adrianople in June. The imperial army was defeated, while Leo the Armenian fled from the battle. With conspiracy in the air, Michael preempted events by abdicating on 11 July 813 in favor of the general Leo the Armenian and becoming a monk (under the name Athanasios). His sons were castrated and relegated into monasteries, one of them, Niketas (renamed Ignatios), eventually becoming Patriarch of Constantinople. Michael died 11 January 844.