(also T. Triasilo). Years of birth and death unknown. Hetman of the Zaporozh’e Unregistered Cossacks from 1629. Leader of a popular uprising against oppression by the Polish szlachta (aristocracy) in the Ukraine.
Fedorovich established ties with Russia and the Don Cossacks. In 1630 he led an antifeudal uprising of peasants and cossacks that spread throughout a considerable part of the Dnieper region. He defeated the Polish troops of Hetman Koniecpolski outside Pereiaslav; however, Koniecpolski succeeded in splitting the ranks of the rebels with promises of benefits and concessions. Fedorovich did not accept the agreement made between the cossack elite and Koniecpolski and went over to the Zaporozh’e Host with some of the rebels.