Accession
In early 1383, Binnya Nwe, not yet 16, eloped with his half-sister Talamidaw and fled to Dagon (Yangon). The king, who was on his deathbed, pardoned both of his children. But the rival claimants to the throne the chief queen, Mahadevi/Smim Maru and Laukpya all wanted to get rid of Binnya Nwe, and sent three armies to Dagon. At Dagon, the young prince, aided by a few loyal forces and Muslim mercenaries, had already fortified the town. Within a few days of siege, two arimes, led by Laukpya and Byattaba (the rebellious governor of Martaban), withdrew, and only the army led by Smim Maru remained. On 14 May 1383 (10th waxing of Nayon 745 ME), Binnya Nwe's forces defeated Smim Maru's. Smim Maru was caught and executed.
On 21 January 1384 (12th waning of Pyatho 745 ME), the young prince now marched to Pegu. When they got to Pegu two days later, Binnya U had just died, and he was at once proclaimed king by the palace officials. He ascended the throne with the reign name of Razadarit (Pali: Rajadhiraj; King of Kings) ten days later on 2 February. He had just turned 16.
At his accession, Razadarit controlled only the Pegu province out of three principal Mon regions in lower Burma. The Martaban region was ruled by Byattaba, and the Irrawaddy delta was under the rule of Laukpya of Myaungmya. Razadarit pardoned his aunt Mahadevi and gave her Dagon in fief but he could not buy his uncle Laukpya's loyalty. Laukpya, who had always ruled his fief like a king under his brother Binnya U, was not prepared to submit to his teenage nephew. In 1385, as Razadarit prepared to march to the delta, Laukpya sought assistance from King Swasawke of Ava with the promise of submission to Ava. Swasawke's acceptance of Laukpya's invitation resulted in the Forty Years' War between Ava and Pegu.
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