The earliest reference of the proto-Vietnamese or the Vietic in Chinese annals was the "Lạc" (Chinese: Luo), "Lac Viet", or the Dongsonian, an ancient ethnic group of Mon-Khmer (Austroasiatic) stock occupied the Red River Delta. The Lạc developed the sophisticated metal age Dong Son Culture and the Văn Lang chiefdom, ruled by the semi-mythical Hùng kings. To the south of the Dongsonians was the Sa Huynh Culture of the Austronesian proto-Cham people. Around 400–200 BC, the Lạc came to contact with the Âu Việt Tai people and the Sinitic people from the north. According to a late third or early fourth century AD Chinese chronicle, the leader of the Âu Việt, Thục Phán, conquered Văn Lang and deposed the last Hùng king. Having submissions of Lạc lords, Thục Phán proclaimed himself King An Dương of Âu Lạc kingdom.