Somdetch Brhat-Anya Fa Ladhuraniya Sri Sadhana Kanayudha Maharaja Brhat Rajadharana Sri Chudhana Negara, better known as Fa Ngum (Laotian: ຝ້າງູ່ມ [fȁːŋum]; 1316 – 1393, born in Muang Sua, died in Nan), established the Lao kingdom of Lan Xang in 1354.
Fa Ngum conquered western Nghệ An as well as the valleys between Red River and Black River in Vietnam (Tonkin) and modern day Isan in Thailand. In 1352–1354, he conquered Muang Sing, Muang Houm, Chiang Hung, Pak Ou and Pak Beng. In 1353, he conquered Vietiane, Xiang Khoang and then Luang Phrabang. He fought the ultimate battle against his uncle near Xiang Dong Xiang Thong and won, becoming the undisputed master of the land, which he named Lan Xang and in keeping with his Khmer wife's wishes, made Theravada Buddhism the state religion.