This is the Chinese region that served as a military and political battleground between Japan.

The Chinese region that you're referring to is Manchuria. This area, located in the northeast part of China, was a significant military and political battleground between China and Japan, particularly during the first half of the 20th century. In 1931, Japan invaded and occupied Manchuria following an event known as the Mukden Incident. This led to the establishment of the Japanese puppet state called Manchukuo in 1932. The occupation continued until the end of World War II, when Soviet forces entered Manchuria and Japanese forces surrendered in 1945. Manchuria was then returned to Chinese control.

Manchuria is a historically and strategically important region due to its rich natural resources, which include coal and iron ore—vital for industrialization. The Japanese invasion of Manchuria marked the beginning of their aggressive expansion throughout Asia and was a precursor to the wider conflicts of the Second World War in the Pacific theater. Its occupation was characterized by harsh military rule and exploitation of resources and led to significant resistance from both Chinese nationalists and communists.

The events in Manchuria had far-reaching consequences, contributing to the eventual downfall of the League of Nations due to its inability to stop Japanese aggression. Furthermore, the resistance in Manchuria also laid some of the groundwork for the Chinese Civil War between the Communist Party of China and the Nationalist Party (Kuomintang), which resumed after the end of World War II and led to the establishment of the People's Republic of China in 1949. The history of Manchuria during this period is a powerful example of how regional conflicts can have significant global impacts and alter the course of world history.