Hu? originally rose to prominence as the capital of the Nguy?n Lords, a feudal dynasty which dominated much of southern Vietnam from the 17th to the 19th century. In 1775 when Tr?nh S?m captured it, it was known as Ph? Xu?n. In 1802, Nguy?n Ph?c ?nh (later Emperor Gia Long) succeeded in establishing his control over the whole of Vietnam, thereby making Hu? the national capital. Hu? was the national capital until 1945, when Emperor B?o ??i abdicated and a communist government was established in H? N?i (Hanoi), in the north. While B?o ??i was briefly proclaimed 'Head of State' with the help of the returning French colonialists in 1949, his new capital was S?i G?n (Saigon), in the south.