Was the Great Depression the main reason Japan attacked Manchuria in 1931? Explain your answer.

The Great Depression was certainly one of the reasons. Prior to the Great Depression, Japan had been dependent on trade for its economic well-being. This was unavoidable, given Japan's lack of natural resources. However, with the Great Depression affecting the world economy as a whole, many countries started to introduce protectionist measures. This badly affected Japan's trade relations with many countries, including the US. Japanese industries could no longer get cheap supplies of nature resources and markets to sell its goods. This prompted Japan to view Manchuria as a solution to their economic problems, since Manchuria could provide cheap labour, raw materials (coal, timber and iron) and an overseas market for Japanese products.

The rise of militarism in Japan in the early 1930s also contributed to the Japanese aggression towards Manchuria. The civilian government in Tokyo became dominated by military personnel as the civilian government appeared to be helpless in solving Japan's problems. The Japanese military, on the other hand, was well-respected by the people and was regarded as the group capable of solving Japan's problems. For the military leaders, they saw the expansion of Japanese territories as the solution of Japan's economic problems as well as a way to increase Japanese prestige. Manuchuria was near to Japan and China was too involved in an internal conflict to defend the area. Thus, it became a logical target for Japanese military government to start their expansion policy.

The attack on Manchuria was also Japan's first step towards building an empire. This was viewed necessary in order to prove to the West that Japan was a great power . It aimed to create the 'Greater East Asia Co-Prosperity Sphere' which would include China, Southeast Asian countries and even India. By taking over Manchuria, Japan could prepare for its next invasion of China and subsequently, Southeast Asian countries.