Territorial principalities in both Insular and Mainland Southeast Asia, characterised as "Agrarian kingdoms" had by around 500 BCE developed an economy based on surplus crop cultivation and moderate coastal trade of domestic natural products. Several states of the Malayan-Indonesian "thalassian" zone shared these characteristics with Indochinese polities like the Pyu city-states in the Irrawaddy river valley, Van Lang in the Red River delta and Funan around the lower Mekong. Văn Lang, founded in the 7th century BCE endured until 258 BCE under the rule of the Hồng Bàng dynasty, as part of the Đông Sơn culture eventually sustained a dense and organised population, that produced an elaborate Bronze Age industry.