August 25 in History
1630 – Portuguese forces are defeated by the Kingdom of Kandy at the Battle of Randeniwela in Sri Lanka
In the Sinhalese–Portuguese War, the Battle of Randeniwela, between the Portuguese forces commanded by then-Governor Constantinu De Sá de Noronha and Kandyan forces led by King Senarth’s youngest son, Prince Maha Astana, was fought at Randeniwela near Wellawaya, a place close to the town of Badulla, on this day in 1630. The Portuguese army suffered a complete rout subsequent to a mass defection by its Lascarin (local militia) contingent and a rain of arrows and bullets, in the night, against which it was impossible for the Portuguese to erect any protection. Into the bargain, the torrential rain that poured down drenched the Portuguese army for several hours rendering the gunpowder and matches of their arquebuses useless. Prince Maha Astana would later become Rajasinghe II.
-Wikipedia