Amethyst incident

The Amethyst incident, also known as the Yangtze incident, was an historic event that occurred on the Yangtze River for three months in the summer of 1949, during the late phase of the Chinese Civil War. The incident involved the Communist People's Liberation Army (PLA), who were in the middle of a river-crossing offensive to overthrow the Nationalist Government, and British Royal Navy ships HMS Amethyst, HMS Black Swan, HMS Consort and HMS London. The British warships, whose right of passage along the Yangtze had been unchallenged previously since the late Qing dynasty, came under bombardment by PLA artillery and were forced to withdraw permanently from Chinese territorial waters.

The incident has been widely celebrated in the communist People's Republic of China as a milestone incident that marked the end of Western gunboat diplomacy in China and as one of the last nails in the coffin for the Century of Humiliation.