John the Eunuch (Greek: Ιωάννης Ευνούχος) was a dignitary of the Empire of Trebizond who lived during the first half of the 14th century.
John played an important role in the internal affairs of the Empire of Trebizond until his assassination in March 1344.
[2] The megas doux John is first mentioned in connection to the rise to the throne of Basil Grand Komnenos (r. 1332–1340), following the brief reigns of Andronikos III (r. 1332) and Manuel II (r. January – September 1332).
According to information related by Michael Panaretos, on 21 February 1333 the megas doux John participated in the events during which the recently deposed emperor Manuel II was murdered.
[4] A few years later the eunuch John was involved in the Trapezuntine Civil War, supporting Irene Palaiologina.