The Ahom dynasty (1228–1826) ruled the Ahom Kingdom in present-day Assam, India for nearly 598 years. The dynasty was established by Sukaphaa, a Shan prince of Mong Mao (present-day Yunnan, China) who came to Assam after crossing the Patkai mountains. The rule of this dynasty ended with the Burmese invasion of Assam and the subsequent annexation by the British East India Company following the Treaty of Yandabo in 1826. In external medieval chronicles the kings of this dynasty were called Asam Raja, whereas the subjects of the kingdom called them Chaopha, or Swargadeo (in Assamese). Chao-Pha The office of the Ahom king, was reserved exclusively for the descendants of the first king Sukaphaa (1228–1268) who came to Assam from Mong Mao in 1228. Succession was by agnatic primogeniture. Nevertheless, following Rudra Singha's deathbed injunction four of his five sons became the king one after the other. The descendants of Sukaphaa were not eligible for ministerial positions—a division of power that was followed till the end of the dynasty and the kingdom. When the nobles asked Atan Burhagohain to become the king, the Tai priests rejected the idea and he desisted from ascending the throne. The king could be appointed only with the concurrence of the (council of ministers—Burhagohain, Borgohain, Borpatrogohain, Borbarua and Borphukan). During three periods in the 14th century, the kingdom had no kings when acceptable candidates were not found. The ministers could remove unacceptable kings, and it used to involve executing the erstwhile king. In the 17th century a power struggle and the increasing number of claimants to the throne resulted in kings being deposed in quick succession, all of whom were executed after the new king was instated. To prevent this bloody end, a new rule was introduced during the reign of Sulikphaa Lora Roja—claimants to the throne had to be physically unblemished—which meant that threats to the throne could be removed by merely slitting the ear of an ambitious prince. Rudra Singha, suspecting his brother Lechai's intention, mutilated and banished him. The problem of succession remained, and on his deathbed, he instructed that all his sons were to become kings. One of his sons, Mohanmala Gohain, was superseded, who went on to lead a rebel group during the Moamoria rebellion. The later kings and officers exploited the unblemished rule, leading to weak kings being instated. Kamaleswar Singha (2-year-old son of Kadam Dighala) and Purandar Singha (10-year-old