Northumbria's power begins to wane after 685…

Thadominbya establishes the Upper Burmese kingdom of Ava in 1364 following the collapse of the Sagaing and Pinya Kingdoms due to raids by the Shan States to the north.

Ava, viewing itself as the rightful successor to the Pagan Kingdom, tries in its first years of existence to reassemble the former empire by waging constant wars against the Mon Hanthawaddy Kingdom in the south, the Shan States in the north and east, and Rakhine State in the west.

Thadominbaya dies childless of smallpox at twenty-one in 1368; his widowed queen and her soldier-bridegroom seize power, but opposition government ministers instead support the thirty-seven-year-old Swasawke, who soon evicts the usurping couple, ascends Ava’s throne as king, and settles the border war with Pegu in 1371.

The region of present Burma, or Mynamar, had divided in the fourteenth century into a number of rival kingdoms, chief of which are Ava in Upper Burma and Pegu in Lower Burma.

These two states, while warring with each other, also fight Toungoo (a state on the Ava-Pegu frontier), the neighboring Shan people, and the Arakan kingdom on the west coast.

Since 1369-1539, Hanthawaddy has been the capital of the Mon Kingdom of Ramanadesa.

A succession dispute following the death of Ava’s King Minyekyawswa in 1401 enables Pegu’s King Rajadhirat, or Razadarit, to launch several attacks against his northern neighbor.

His flotilla sails up the Irrawaddy river in 1406 and, despite defeats suffered en route, manages to reach and settle outside the town walls of Sagaing, across the river from Ava.