Stolberg won the Rostov-on-Don City championship in 1938. The next year he took second in a Soviet master candidates tournament. In 1940, Stolberg shared first with Eduard Gerstenfeld in Kiev (the 12th USSR-ch semi-final), and tied for 13-16th in Moscow (the 12th USSR Chess Championship won jointly by Andor Lilienthal and Igor Bondarevsky). In June 1941, Stolberg was in fourth place in Rostov-on-Don (the 13th USSR-ch semi-final), when the German attack on the Soviet Union interrupted the event.