They left much of it before the end of the war as the USSR invaded with 1.5 million troops. After the war Manchuria reverted to China, from which Japan had seized it in 1931-32. They left it because it wasn't theirs and they lost the war.
Because they were attacked by the Japanese.
When a country loses a war, they must return everything they had taken.
Japan surrendered, ending WW2. They surrendered from the atom bomb that was dropped on Japan.
Manchuria
Japanese invasion of Manchuria
Manchuria was neither. It was invaded by Japan in the 1930's and was under Japanese occupation during the war.
According to official Japanese Government data, at the end of World War II Japan had 1,719,700 Army and 70,700 Navy personnel stationed in China and Manchuria. In addition to these, there were also approximately 1 million Chinese collaborationist troops in those territories that had allied themselves with the Japanese. Total Japanese military deaths in China and Manchuria over the course of World War II totalled 502,400.
Japan's incursion into Manchuria.
Manchuria
Under the conditions of the Japanese surrender, they removed all of their occupation forces from Korea, which they had occupied since the Russo-Japanese War of 1905. Russian forces defeated the Japanese army in Manchuria in mid-August 1945, and some of these Japanese remained prisoners until the 1950s.
At the begining of World War 2 they invaded Indochina (Vietnam).
Manchuria
Japanese invasion of Manchuria
Manchuria
Manchuria was neither. It was invaded by Japan in the 1930's and was under Japanese occupation during the war.
According to official Japanese Government data, at the end of World War II Japan had 1,719,700 Army and 70,700 Navy personnel stationed in China and Manchuria. In addition to these, there were also approximately 1 million Chinese collaborationist troops in those territories that had allied themselves with the Japanese. Total Japanese military deaths in China and Manchuria over the course of World War II totalled 502,400.
Japan's incursion into Manchuria.
Japan invaded Manchuria in 1931 as a part of a larger strategy of territorial expansion, mostly for its resources. The US and Japan would not be engaged in World War 2 for another 10 years.
Prior to the outbreak of World War II, Imperial Japan completed their seizure of the Chinese province of Manchuria in early 1932. The occupation-invasion began in September of 1931 through an incident staged by Japanese military personnel.
The First World War was a contributing factor to starting the Second World War, but for the Japanese and a part of China called Manchuria, to the west, the War started in 1931.