6. Japan had extensive holdings in China before the invasion of Manchuria
During the First World War, Japan was one of the Allies, and as a consequence of Germany’s defeat, the latter country’s extensive holdings in China were granted to Japan as war reparations. Japan moved to occupy them militarily, an action which caused concern among the western nations, particularly Great Britain and the United States. In 1929 a dispute between China and the Soviet Union over control of the Chinese Eastern Railway led to the Chinese seizing the railroad. The Soviets responded with a military force of over 150,000 men, which deployed along the border with Manchuria.
The Soviets won a quick victory, established the principle of status quo ante Bellum, and withdrew. Most of the western world supported the Soviet actions. The Japanese military took note of the capabilities of the modernized Soviet army and the relative ease with which they had defeated the Chinese. Senior Japanese military leaders and their industrial and nationalist supporters saw an opportunity to expand their influence within the government and the Japanese empire in the name of the emperor. What was needed was an excuse to act without appearing to the League of Nations (of which Japan was a member) to be the aggressor.
