Oleinikov Ya. T. in 1927 was drafted into the ranks of the Soviet Army, enlisted as a cadet in the regimental school of the 38th rifle regiment of the 13th rifle division of the North Caucasian Military District. The regiment was stationed in Millerovo. In July 1932, at his own request, he filed a report for long-term service. He took retraining courses, in 1939 the regiment was sent to Estonia, in 1941 he was appointed secretary of the party commission at the political department. He fought on the North-West and Leningrad fronts. Awarded with: Orders of the Red Banner, Red Star, Lenin and medals "For Military Merit", "For the Defense of Leningrad", "For Victory over Germany", "30 Years of the Soviet Army and Navy".