A brief conflict between China and the Soviet Union over possession of an island in the Ussuri River. The exact position of the border between north-east China and the Soviet Union had long been a subject of dispute. The disagreement turned into a military confrontation because of the ideological dispute between China and the Soviet Union after 1960 and the militant nationalism that was part of the Cultural Revolution. In March 1969 two battles were fought for possession of the small island of Zhen Bao (also known as Damansky). The Chinese ultimately retained control of the island, and talks in September 1969 brought the crisis to an end.