Ba Cụt and his forces fought the Vietnamese National Army (VNA), the Việt Minh, and the Cao Đài religious movement from 1943 until his capture in 1956. Known for his idiosyncrasies, he was regarded as an erratic and cruel leader who fought with little ideological purpose. His sobriquet came from the self-amputation of a finger as part of a vow during his teenage years to defeat the French colonial forces; he later swore not to cut his hair until the communist Việt Minh were defeated. Ba Cụt frequently made alliances with various Vietnamese factions and the French. He invariably accepted the material support offered in return for his cooperation, and then broke the agreement—nevertheless, the French made deals with him on five occasions. The French position was weak because their military forces had been depleted by World War II, and they had great difficulty in re-establishing control over French Indochina, which had been left with a power vacuum after the defeat of Japan.
In mid-1955, the tide turned against the various sects, as Prime Minister Ngô Đình Diệm of the State of Vietnam and his VNA began to consolidate their grip on the south. Ba Cụt and his allies were driven into the jungle, and their position was threatened by government offensives. After almost a year of fighting, Ba Cụt was captured. He was sentenced to death and publicly beheaded in Cần Thơ.