Bayinnaung Takes Ayutthaya and Rules a Vast Empire

On 12 January 1554, the Toungoo commander Bayinnaung was crowned king at his new royal seat of Pegu, taking the reign title Thiri Thudhamma Yaza. Born Ye Htut in 1516, his ancestry remains historically disputed. While the eighteenth-century royal chronicle Maha Yazawin claimed he descended from ancient regional dynasties, early twentieth-century traditions asserted that his father was a humble toddy palm climber. Regardless of his background, he was raised within the royal court alongside the heir Tabinshwehti. After Tabinshwehti ascended the throne in 1530, the two men expanded their realm through aggressive military campaigns. When Tabinshwehti fell to assassins in 1550, the nascent empire fragmented, forcing Bayinnaung to systematically subdue rival claimants and reclaim control over central and Lower Burma.

Bayinnaung transformed the Toungoo polity by integrating imported military technology with unprecedented regional levies. Coastal trade gave him access to Portuguese matchlocks, cannon, and foreign mercenaries, which he deployed alongside large contingents of infantry, cavalry, and war elephants. Rather than relying solely on local recruits, he required defeated territories to furnish soldiers for subsequent expeditions, allowing him to field armies that numbered tens of thousands. With these expanded forces, he captured the rival capital of Ava in January 1555, ending the longstanding dominance of the Confederation of Shan States over the upper Irrawaddy valley.