During the Great Purge, Stepanov's colleague division commissar Peter Maximovich Feldman (standing to his left in the group photo behind Alexander Yegorov) was executed on August 22, 1938.
On November 28, 1938, the Central Committee of the Communist Party of the Soviet Union made the decision to dismiss Stepanov from the military, which was carried out the next day.
Stepanov was born in August 1893 in the village of Novaya, Suzhdalsky Uyezd, Vladimir Governorate to a peasant family.
Stepanov was arrested on 9 December 1938, and sentenced to twenty years of imprisonment in the gulag on 31 May 1939, charged with participating in a military conspiracy.
[1] According to an account by historian Michael Parrish, on 30 March 1939, Stepanov wrote a letter to Kliment Voroshilov in which he told him that between 40 and 45 percent of chemical officers serving in military districts and 60 to 65 percent of those with corps and divisions had been arrested in the Great Purge.