Mingyi Swa of Prome was viceroy

Viceroy

A viceroy is a royal official who runs a country, colony, or province in the name of and as representative of the monarch. The term derives from the Latin prefix vice-, meaning "in the place of" and the French word roi, meaning king. A viceroy's province or larger territory is called a viceroyalty...

 of Prome of Ava Kingdom

Ava Kingdom

The Ava Kingdom was the dominant kingdom that ruled upper Burma from 1364 to 1555. Founded in 1364, the kingdom was the successor state to the petty kingdoms that had ruled central Burma since the collapse of Pagan Empire in the late 13th century...

 from 1446 to 1482. He was made governor of Prome in 1446 by his father Narapati of Ava. He raised a rebellion when his eldest brother Thihathura I succeeded the Ava throne in 1469. But Thihathura laid siege on Prome, and Mingyi Swa submitted to his brother. He was forgiven, and reappointed to his former position.

Mingyi Swa died in 1482, after 36 years of rule at Prome. After his death, his younger brother Thado Minsaw

Thado Minsaw of Prome

Thado Minsaw of Prome was the founder of Prome Kingdom, who reigned the minor kingdom from 1482 to 1527. He was governor of Tharrawaddy during the reigns of his father King Narapati of Ava and his elder brother King Thihathura. After Thihathura died in 1481, the new king Minkhaung II was greeted...

, who was governor of Tharrawaddy

Tharrawaddy

Tharrawaddy is a town and district of the Bago Division of lower Myanmar....

, seized the Prome chieftainship, raised a rebellion against his nephew King Minkhaung II

Minkhaung II

Minkhaung II was the twelfth king of Ava who reigned from 1481 to 1502. His 20-year reign was the beginning of the decline of Ava's hold on Upper Burma. Yamethin, a region to the east of Ava, revolted upon Minkhaung's ascension to the Ava throne and stayed independent throughout Minkhaung's reign...

. The rebellion succeeded, and Prome became independent.