Âu Lạc (Hán tự: 甌貉/甌駱; pinyin: Ōu Luò; Wade–Giles: Wu1-lo4 Middle Chinese (ZS): *ʔəu-*lɑk̚ < Old Chinese *ʔô-râk) was a supposed polity that covered parts of modern-day Guangxi and northern Vietnam. Founded in 257 BCE by a figure called Thục Phán (King An Dương), it was a merger of Nam Cương (Âu Việt) and Văn Lang (Lạc Việt) but succumbed to the state of Nanyue in 179 BCE, which, itself was finally conquered by the Han dynasty. Its capital was in Cổ Loa, present-day Hanoi, in the Red River Delta.
An Dương Vương
According to folklore, prior to Chinese domination of northern and north-central Vietnam, the region was ruled by a series of kingdoms called Văn Lang with a hierarchical government, headed by Lạc Kings (Hùng Kings), who were served by Lạc hầu and Lạc tướng. In approximately 257 BCE, Văn Lang was purportedly annexed by the Âu Việt state of Nam Cương. These Âu Việt people inhabited the southern part of the Zuo River, the drainage basin of You River and the upstream areas of the Lô, Gâm, and Cầu Rivers, according to Vietnamese historian Đào Duy Anh. The leader of the Âu Việt, Thục Phán, overthrew the last Hùng kings, and unified the two kingdoms, establishing the Âu Lạc polity and proclaiming himself King An Dương (An Dương Vương). According to Taylor (1983): Our knowledge of the kingdom of Âu Lạc is a mixture of legend and history. King An Duong is the first figure in Vietnamese history documented by reliable historic sources, yet most of what we know about his reign survived in legendary form.
Cổ Loa Citadel
Cổ Loa, the largest prehistoric moated urban settlement in Southeast Asia, was the first political hub of Vietnamese civilization in the pre-Sinitic era, encompassing , and requiring as many as 2 million cubic meters of material. The construction might have begun as early as the fourth century BCE, while the middle phase of construction was between 300 and 100 BCE.