From 1911-1912, signaled the end of the Qing Dynasty. With this, ended China's millennia-long imperial period.
From 1927-1949, a civil war occurred between communist and nationalist. Strife between the two sides led to the creation of The Red Army during the war.
In 1934, Communist began to retreat in a event known as the Long March. Around this time, Mao Zedong was removed from leadership by the Chinese communist Central Committee.
On August 6 1945, the United States dropped the world's first atomic bomb on Japan. There were a total of 2 bombs dropped one deployed at Hiroshima killing 146,000 people and the other was deployed at Nagasaki, killing 80,000 people.
In 1949, The People's Republic of China was declared by Mao. Upon Chiang's defeat, he fled with the remnants of his Nationalist government to Taiwan. Chiang lived out the remainder of his life in Taiwan.
In 1950, Mao and Stalin develop a political relationship in which they are able to negotiate and cooperate with one another. Their relation can be described as a formed 'friendship'.