and defending the country against the possibility of foreign invasion. Eager to dispose of Trotsky's political and military supporters, Stalin directed the execution of eight high-ranking generals between 1935 and 1938. Primary among these was Marshal Mikhail Tukhachevsky, leader of the Soviet invasion of Poland. Despite Stalin's isolationist policies, and even though the Soviet Union's borders would remain static for fifteen years following Lenin's death, the Soviets continued to involve themselves in international affairs, and the Comintern was instrumental in establishing the Communist parties of China in 1921 and Indochina in 1930. Additionally, the Red Army played a crucial role in the Spanish Civil War, supplying over 1,000 aircraft, 900 tanks, 1,500 artillery pieces, 300 armored cars, hundreds of thousands of small arms and 30,000 tons of ammunition to the Republican cause. Soviet participation in the Spanish Civil War was greatly influenced by the growing tension between Stalin and Adolf Hitler, the leader of Nazi Germany and an avid supporter of the fascist forces of Francisco Franco. Nazi–Soviet relations were tempered by Hitler's personal hatred for communist ideology and for wanting to expand German territories. Direct armed conflict between Germany and the Soviet Union was delayed by the signing of the Molotov–Ribbentrop Pact on August 23, 1939, which essentially divided the nations of Eastern Europe into two spheres of interest, one belonging to the Soviets and the other to the Nazis. The Soviet Union sold arms to the Governor of Xinjiang province of the Republic of China, Jin Shuren, and help install his successor Sheng Shicai in 1934 as their puppet governor. They intervened militarily in an invasion of Xinjiang against the Chinese Muslims 36th Division (National Revolutionary Army) and Han chinese troops led by the Chinese Muslim General Ma Zhongying and the Han chinese general Zhang Peiyuan when they were on the verge of defeating Sheng's manchurian and white Russian troops. 2 brigades of 7,000 men, armed with tanks, planes, mustard gas, and armored cars were the Soviet forces which invaded. After fierce fighting, in which mustard gas was used by the Soviet Union at the Battle of Tutung, Ma Zhongying retreated and Zhang committed suicide to avoid capture. During the battle, the chinese Muslims reportedly dressed up in sheepskins and stormed Soviet machine guns posts with swords. Ma encountered a Red Army column at the Battle of Dawan Cheng and wiped out the entire column, his Muslim troops