Oral traditions trace the origins of the Mimika people to conflict over sago groves among four local groups living in the lowlands east of the Utakwa River. An exodus to the southwest triggered a chain reaction among other groups in the east moving to the west. Linguistic evidence does point to a genetic relationship between Asmat (east of Mimika), and Sentani, far to the northeast on the north coast of Irian Jaya, thus suggesting a possible prehistoric northeast-southwest migration. Historic contacts with foreigners began perhaps as early as A . D . 1600, with Chinese, Indonesian, and Dutch Traders entering the area from the west via Etna Bay. In the early twentieth century, while the area was under Dutch administration, Ceramese Islamic traders appointed nominal local representatives ( radjas ) in western Mimika, leading to a rush for ironware, textiles, earrings, and beads in exchange for resin, local foods, and slaves. In general, attitudes towards foreigners passed through several stages: enmity and cautious rapprochement; goodwill inspired by a strong desire for Western commodities; disappointment and passive resistance to interference with a seminomadic way of life; and, finally, following Japanese occupation during World War II, coexistence and resignation to the strangers' permanent presence. The entire Mimika population has now been baptized, but due to a paucity of marketable resources, economic development has been slow.