Career
He lost the southern territories of Tenasserim coast back to his nominal overlord Sukhothai, and looked to expand his territory northwards. He died in battle in his siege of Prome (Pyay). Saw Zein moved the capital of kingdom from Martaban (Mottama) to Pegu (Bago) in the north, leaving Martaban with a strong garrison.
lieutenant is not clear if the move was precipitated by his overlord Sukhothai"s reoccupation of the Tenasserim (Taninthayi) coast.
At Pegu, Saw Zein consolidated his hold over the Irrawaddy delta, and looked to expand northwards into Upper Burma. He died trying. In 1330, he attacked Prome, a strategically located city and appeared to have been held by an independent king, with a large army and flotilla.
The king was killed in battle, and his forces were defeated. Like his predecessors, Saw Zein was also of Shan and Mon descent.
(He was at least a quarter Shan as his mother Hnin U Yaing, sister of King Wareru, was half-Shan Participant of his name Saw was the Shan honorific Sao).
