The event you're describing is called the Ra pe of Nanking. It happened in 1937. Around 50,000 innocent Chinese people were killed by Japanese troops.
Ratification by China, France, theSoviet Union, the United Kingdom, the United States and by a majority of the other signatory states. The Charter of the United Nations (also known as the UN Charter) of 1945 is the foundational treaty of the United Nations, an intergovernmental organization.
hopefully this helps
The nations had different systems of government and different economic systems. The USSR hated the U.S and it's capitalism, hoping to one day crush it but with the fall of the USSR in 1991, It was a monumental victory for capitalism over communism and socialism.
The three countries were
Northern and Western Europe and the Great Britain