Emperor Taiwu of Northern Wei
The first Disaster of Wu started in 446, when Emperor Taiwu of Northern Wei, a devout Taoist who followed the Northern Celestial Masters, was fighting the Xiongnu rebel Gai Wu (蓋吳). During the campaign, weapons were located in Buddhist temples, and he therefore believed that Buddhists were against him. With encouragement from his also devoutly Taoist prime minister Cui Hao, Emperor Taiwu ordered Buddhism abolished under penalty of death, and slaughtered the Buddhists in the Guanzhong region, the center of Gai's rebellion. The ban against Buddhism was relaxed in Emperor Taiwu's later years, and formally ended after his grandson Emperor Wencheng of Northern Wei, a Buddhist, took the throne in 452.