The Chinese Civil War was fought from the late 1920s until 1950. It was fought between the communist forces of Mao Zedong and the nationalist forces of Chiang Kai-Shek. It ended with the communists in control of mainland China and the nationalist forces forced to flee and establish a government in Taiwan. This situation, of a divided China, persists to this day.

China and the Soviet Union were both allied with North Korea in their war against South Korea and the United States of America. The Korean War was fought from 1950 to 1953 and ended in a virtual stalemate.

The Rape of Nanking took place in 1937 when forces of the imperial Japanese army captured the Chinese capital Nanking. It featured the wholesale rape, slaughter, and massacre of the Chinese population by Japanese troops. The recriminations from this, and other war crimes committed by the Japanese in China and East Asia, continue to affect relations between these countries to this day.

The Russo-Japanese War is often seen as a turning point in history because it was the first time a modern eastern power had defeated a western power in open warfare. The previous centuries had been marked by one victory after another for the west, but with victory in the Russo-Japanese War this trend was halted.

The German military tactic of blitzkrieg was first employed in the German invasion of Poland in 1939. Blitzkrieg involves the rapid movement of an attacking force comprised of armored vehicles and mechanized infantry. It is designed to disorient the enemy and result in a quick and comprehensive victory.

All of these countries were occupied by the Soviet Union at the end of World War II except Austria. Austria remained a part of Western Europe and a feature of the capitalist bloc of NATO, whilst Poland, Hungary, Romania, and Czechoslovakia all became part of the communist bloc of the Warsaw Pact.

The foundations for the Korean War were laid at the end of the Second World War when the Soviet Union occupied Japanese controlled North Korea and the United States occupied Japanese controlled South Korea. By 1950 it became clear that two separate governments were competing in Korea, a communist north and a capitalist south. This led to open warfare when the North Korean army, backed by the Soviet Union and China, invaded South Korea. The United States of America provided for the defense of South Korea, along with a coalition of many other western capitalist nations.

The United States was fighting against the Vietcong and the forces of the Northern Vietnamese communist government. The war ended with the United States withdrawing before it had achieved its goals, and the subsequent unification of the country under the control of the Northern Vietnamese communist government.

Ho Chi Minh led the communist forces of North Vietnam during the Vietnam War (1955- 1975). He was instrumental in the foundation of the Democratic Republic of Vietnam and led the North Vietnamese Army and the Viet Cong. He first defeated the French at the battle of Dien Bien Phu in 1954 and later the coalition forces, which were led by the United States. 

The USSR (known today as Russia) was the Communist leader during the Cold War was the world was split between communism and free enterprise ideas.