This is the chinese region that was a military and political battleground between japan

Manchukuo

Explanation:

The state of Manchuria formed in the year 1934 was a state of the empire of the japan on the northeastern china and inner Mongolia and was founded in 1932 after the japans invasion and in 1934. Later got to be known as a constitutional monarchy earlier it was a homeland of the Qing dynasty and later was seized by the japan at the end of the WW II and first were seized b the soviet invasion in august.