Of Pagan royalty, Uzana inherited a disunited kingdom, which fell apart right after his predecessor Thihathu's death.
Even in his core power base in present-day central Myanmar (Burma), Uzana faced a serious rival in his half-brother Kyawswa.
Born in June 1298,[note 1] Uzana was the biological child of King Kyawswa of Pagan (r. 1289–97) and Queen Mi Saw U.
By his birth, his father had been dethroned for six months, and his mother had been taken by Thihathu, one of the three brothers and former Pagan generals who overthrew Kyawswa.
[1] Adopted at birth by Thihathu, co-regent of the newly founded Myinsaing Kingdom,[1] Uzana never knew his biological father who was executed on the orders of the three regents in 1299.
[2] The young prince grew up in Pinle with Thihathu's children: his two maternal half-siblings Kyawswa and Nawrahta as well as his step-siblings Tarabya, Saw Yun and Saw Pale.
[3] Perhaps because of his Pagan royal descent, Uzana grew up being a key scion of the Myinsaing ruling house.
In the same coronation ceremony, he also pronounced Mi Saw U, daughter of King Narathihapate, his chief queen consort, and Uzana his heir-apparent.
In particular, Saw Yun, whose mother was a commoner, resented being treated as a second-class royal, not only behind his stepbrother Uzana but also behind his half-brother Kyawswa.
[7] Even then, Saw Yun still resented that he was not allowed to command as large a force as Uzana or Kyawswa, and that he had to constantly beg for cavalry and war elephants from his brothers.
Back at the Pinya Palace, Thihathu treated a defeated Uzana with contempt, saying he had failed the test.
In 1317–18, Uzana and Kyawswa with a combined force marched to Toungoo, and got its ruler Thawun Nge to submit.
Though Uzana remained the official crown prince, Saw Yun was already the de facto ruler of the northern country.
Indeed, his main rival was not Saw Yun but his half-brother Kyawswa, who openly held court at Pinle, just a few miles away from Pinya and also in the all important Kyaukse region.
Pinya took no action with the 1325 assassination of Saw Hnit, the Pinya-recognized ruler of Toungoo, and had to be satisfied with the usurper Kayin Ba's nominal submission.