The 1861 Xinyou coup at Rehe
When the Xianfeng Emperor died in exile at Rehe in 1861, he left his five-year-old son under eight regents led by Sushun. The boy's mother, the concubine Cixi, allied with the senior Empress Dowager Ci'an and the emperor's half-brother Prince Gong. Because the two widows held the seals needed to validate edicts, they could arrest the regents on returning to Beijing: Sushun was beheaded, two others were forced to kill themselves, and Cixi began ruling in the child's name.