Hello Bankei, David, all,
This might be of interest:
Pali tradition states (in the Samantapasadika 69.10, translated by N.A. Jayawickrama, p.61)
that Emperor Asoka sent the monks Sona and Uttara to Suvannabhumi and that they established the Buddhadhamma
there. On that occasion, 3500 noble men and 1500 women entered the Buddhist order. Suvannabhumi has been identified with Lower Burma. The city of Thaton has been identified with Sudhammanagara, the capital of a Mon kingdom of that time.
From archaeological remains, including stone inscriptions in Pali found in Lower Burma, we know that the Pyu people living there before the Burmese arrived were Theravada Buddhists. http://www.enabling.org/ia/vipassana/Ar ... moser.html