[2] In 1192/93, Isaac II named him fleet commander (doux tou stolou) and governor of Philippopolis, an area then suffering from the ongoing Vlach–Bulgarian rebellion.
He began sounding out his subordinate commanders and other men of prominent birth from the wider region, and had himself proclaimed emperor.
[3][4] Immediately he set out with his supporters for Adrianople, seat of his brother-in-law, the Grand Domestic of the West, Basil Vatatzes.
Isaac II harboured his doubts about their sincerity, but chose to overlook their part in the failed uprising.
[4][5] According to Choniates, this deed greatly encouraged the Bulgarian rebels, who had feared Constantine's ability and much preferred the ineffective Isaac II to remain on the throne, if possible, for ever.