Thonburi was capital of Thailand for a short time during the reign of King Taksin, after the previous capital Ayutthaya was sacked by the Burmese. King Rama I moved the capital to Bangkok in 1782 to the other side of the Chao Phraya River. Thonburi stayed an independent town and province, and was merged into Bangkok in 1972.

Thonburi stayed less developed then the original Bangkok part of the city, several of the traditional small waterways (Khlongs) still exist there, which are nearly gone on the other side of the river.