Little archaeological evidence exists for the Chimbu area proper, but data from other highland areas suggest occupation as long as 30,000 years ago, possibly with agriculture developing 8,000 years before the present. It is believed that the introduction of the sweet potato ( Ipomoea batatas ) about 300 years ago allowed for the cultivation of this staple food at higher altitudes with a subsequent increase in the population of the area. Oral traditions place the origin of the Chimbu at Womkama in the Chimbu Valley, where a supernatural man chased away the husband of the original couple living in the area and fathered the ancestors of the current Chimbu tribal groups. First Western contact occurred in 1934 when an Expedition, led by gold miner Michael Leahy and Australian patrol officer James Taylor, passed through the area, and soon afterward an Australian government patrol post and Roman Catholic and Lutheran missions were established. The initial years of colonial administration were marked by efforts to curtail tribal fighting and establish administrative control in the area. Limited government resources and staff made this goal difficult, and by the beginning of World War II only a tenuous peace had been imposed in parts of Simbu. Following the war, Australian efforts to extend and solidify administrative control continued, local men were recruited as laborers for coastal plantations, and coffee was introduced as a cash crop. Establishment of elected local government Councils after 1959 was followed by representation of the area in a territorial (later national) legislative body and by the creation of a provincial legislature. Local tribal politics remain Important and tribal affiliation greatly influences the participation in these new political bodies.