TIMELINE - Relations between China and the United States

REUTERS - U.S. President Barack Obama is in China, seeking to draw the two big powers closer. Here is a timeline of U.S.-Chinese relations since 1949:

October 1949 - People's Republic of China founded by the Chinese Communist Party. The United States keeps diplomatic ties with defeated Nationalist forces who fled to Taiwan, claiming their Republic of China as the sole legitimate government.

1950 - Korean War breaks out with the United States and China sending forces to support rival sides in fighting that lasts until 1953.

1958 - China shells islands between the mainland and Taiwan, held by Nationalist forces, escalating tensions with the United States, which maintains forces on Taiwan.

1960s - United States pursues deepening military involvement in Vietnam, while China more quietly backs Vietnamese Communist forces fighting the U.S.-backed government in the south.

1969-1970 - Secretive and long-moribund back-channel contacts between China and the United States resume as President Richard Nixon and Mao Zedong explore ways to improve relations.

April 1971 - "Ping-pong diplomacy" when China invites U.S. table tennis players to visit, generating a burst of goodwill.

1971 - Nixon's national security advisor, Henry Kissinger, visits China twice, secretly in July and openly in October.

February 1972 - President Richard Nixon visits China, meets ailing Chairman Mao and Premier Zhou Enlai and both sides set out principles for relations between the two nations.