The second son of King Kyawswa of Pagan sought Mongol intervention after his father was overthrown by the Myinsaing brothers in 1297.
[1]: 211 Kumara Kassapa was born to Princess Saw of Thitmahti and Prince Kyawswa, Viceroy of Dala (modern Twante), during the last days of the Pagan Empire.
His father had been handpicked by the dowager queen Pwa Saw to succeed his grandfather King Narathihapate, who was assassinated two years earlier.
In the following years, his authority was increasingly challenged by the three brothers of Myinsaing who led the defense of the Irrawaddy valley against the Mongol invaders in 1283–87.
[9] They changed their mind only after the Myinsaing brothers seized two southernmost Mongol garrisons in northern Burma in January 1300.
They finally sent him to Beijing where on 22 June 1300 the prince was declared the rightful king of Burma by Emperor Temür Khan.