League of Nations

Japan occupied the entire Korean Peninsula, as well as the Manchurian and Jehol regions of China by 1933.

China was invaded in 1931, without declaration of war, when Japan unilaterally annexed Manchuria, i.e. northern China. They then continued with the annexation of the large province of Jehol in 1934. In 1937, Japan launched a full scale invasion into the remaining China. This aggression was part of Japan's policy of liberating Japan from her dependence on foreign states. Japan had a highly developed industry, but hardly any natural resources at all, not even enough to feed themselves in fact. This was not an economic problem, because Japans industry could easily fund all necessary imports, and still generate impressive profits. Just like Japan does today (she still has no significant natural resources). But it was a political problem, or at least the Japanese militarist/nationalist government thought so, because almost all of Asia was in European or US hands. The latter could thus stop deliveries of needed goods and raw materials in order to force Japan to act according to their wishes. Japan therefore pursued a policy of carving an empire for herself on mainland Asia (Korea and China), in order to secure the vast resources of raw materials available there, for her industries and society. She could have just bought them instead, and both Japan and China would have prospered, but Japanese leadership at the time was marked by medieval lines of thought.

Two-fold. Secure Chinese resources for the benefit of Japan. Keep China split between her various warlords so she wouldn't pose a threat to Japanese hegemony over Asia. Answer Technically they didn't. China was invaded in 1931, without declaration of war, when Japan unilaterally annexed Manchuria, i.e. northern China. They then continued with the annexation of the large province of Jehol in 1934. In 1937, Japan launched a full scale invasion into the remaining China. This aggression was part of Japan's policy of liberating Japan from her dependence on foreign states. Japan had a highly developed industry, but hardly any natural resources at all, not even enough to feed themselves in fact. This was not an economic problem, because Japans industry could easily fund all necessary imports, and still generate impressive profits. Just like Japan does today (she still has no significant natural resources). But it was a political problem, or at least the Japanese militarist/nationalist government thought so, because almost all of Asia was in European or US hands. The latter could thus stop deliveries of needed goods and raw materials in order to force Japan to act according to their wishes. Japan therefore pursued a policy of carving an empire for herself on mainland Asia (Korea and China), in order to secure the vast resources of raw materials available there, for her industries and society. She could have just bought them instead, and both Japan and China would have prospered, but Japanese leadership at the time was marked by medieval lines of thought. Answer Japan invaded China to expand their Asian empire to acquire resources to mantain their expansion of their empire. Japan's soldiers commited horrifying acts of barbarity in China, with the indiscriminate torture and killing of civillians, men, women children, no matter what age. In fact, the acts were so horrific, even the Nazis were shocked about what their Japanese allies were doing. Answer Japanese thought of the Chinese as Hitler thought of Jews: inferior. Answer Japan is an island nation and therefore not very rich in resources. China was weak at the time and Japan took advantage of that and invaded China. Also, Japan wanted to take over the whole Asia and China is part of Asia.

to acquire resources.