Anti-Japanese resistance volunteers in China
After the Japanese invasion of Manchuria, and until 1933, large volunteer armies waged war against Japanese and Manchukuo forces over much of Northeast China. Due to Chiang Kai-shek's policy of non-resistance, the Japanese were soon able to establish complete control. After the League of Nations refused to do more than voice its disapproval, there were many small guerrilla organizations which resisted Japanese and Manchu rule: Besides these armies there were other forces under leaders like Lao Pie-fang and others. Zhao Hong Wenguo was influential in supporting some armies such as  the Iron and Blood Army, with many of her children participating in Anti-Japanese insurgent activities. For the whole year of 1932 the Japanese had to occupy themselves with fighting these Chinese forces in various areas of Manchuria. Gen. Ma Zhanshan, nominally in command of them all, had a total fighting force estimated by the Japanese at 300,000 men. Following their defeat, many retreated into Jehol and other places in China. The remainder were forced to disperse their remnants into small units, often called shanlin. Ongoing Japanese "Anti-Bandit" campaigns and other "pacification" measures steadily reduced the number of insurgents . Their numbers declined from 120,000 in 1933 to 50,000 in 1934; 40,000 in 1935; 30,000 in 1936; and 20,000 in 1937. As of September 1938, the number of insurgents was estimated by the Japanese at 10,000. From 1935 the Northeast Anti-Japanese United Army, under the leadership of the Chinese Communist Party, absorbed many of these volunteer forces into its own ranks.