The pioneers of sambo were Viktor Spiridonov and Vasili Oshchepkov . Oshchepkov died in prison as a result of the political purges of 1937 after accusations of being a Japanese spy . Oshchepkov spent much of his life living in Japan and training in judo under its founder Kano Jigoro . The two Russians independently developed two different styles which eventually cross-pollinated and became what is known as Sambo . Compared to Oshchepkov 's judo-based system , then called " Freestyle Wrestling , " Spiridonov 's style was softer and less strength dependent . This was in large part due to Spiridonov 's injuries sustained during World War I
political purges of 1937
Great Purge
Russian martial arts