Myanmar Bago Division is the south of the big central plains. Magway Division and Mandalay Division are to Myanmar Bago north, Kayin State, Mon State and gulf of Mottama are to the east, Myanmar Yangon division is to Myanmar Bago Division's south and Ayeyawaddy, Rakhine State are it's west. The southern part of Myanmar Bago has tropical monsoon climate and northern part has a savannah climate. Myanmar Bago Division has moderate temperature whole year round. The average annual rainfall of Myanmar Bago is 132.36 inches. Pyay and other town have less rain

In the late 1500s, Thanlyin was the base of the Portuguese adventurer, Philip De Brito. Officially a trade representative from Rakhine, he established himself as a local warlord from his base at Thanlyin, and hired his forces on occasion to the Mon in their battles against the Bamar. However, in 1599 he unleased his army against Bago, which he sacked. Captured by the Burmese in 1613, he was executed by impalement, a punishment reserved for defilers of Buddhist temples. Thanlyin continued to be a major port until it was destroyed by King Alaungpaya in 1756 during the Mon revolt.