God Setthathirath He established the capital of Vientiane Xang kingdom was established in 2103 when Xang power loss in the year 2250 Laos became an independent kingdom called Kingdom of Vientiane. Until the year 2321, Thailand's Chao Phraya Chakri. (In the Thonburi) troops to conquer the territory of Laos. Kingdom of Thailand Vientiane became the kingdom since then.