Siege of Sinope in the context of "Kaykaus I"

The Trapezuntine emperors were the rulers of the Empire of Trebizond, one of the successor states of the Byzantine Empire founded after the Fourth Crusade in 1204, until its fall to the Ottoman Empire in 1461. All but two of the Trapezuntine rulers belonged to the Komnenos dynasty, which had previously ruled the Byzantine Empire from 1081 to 1185. They initially claimed to represent the legitimate line of Roman emperors, in opposition to the Latin Empire in Constantinople, the Laskaris dynasty of the Nicene Empire, and the Komnenos Doukas family of Epirus and Thessalonica. To emphasize their dynastic claim, Trapezuntine emperors from the late 13th century onwards styled themselves as Megas Komnenos (Μέγας Κομνηνός, lit. 'Grand Komnenos').

Out of the Byzantine claimants that emerged in 1204 and thereafter, the Trapezuntine emperors, despite their illustrious descent, had perhaps the worst position. Not only were they far away from Constantinople in a peripheral province of the empire, but the reputation of the Komnenoi had been severely damaged by the detested last emperor of the dynasty, Andronikos I Komnenos (r. 1183–1185), grandfather of the first Trapezuntine emperor Alexios I (r. 1204–1222). Though they continued to claim to be the legitimate rulers of the entire former Byzantine Empire for decades thereafter, conflict with the Nicene Empire and the Sultanate of Rum in the early 13th century reduced the power of the Trapezuntine emperors. After the fall of Sinope to Sultan Kaykaus I in 1214, the Empire of Trebizond ceased to be a major contender for restoring the Byzantine Empire and became reduced to a small and local power.