Because the Chambri were a preliterate people, one can only speculate about their history. It is likely that their distant ancestors lived in small, semisedentary hunting and gathering bands. Perhaps in response to the intrusion of those Ndu speakers who became the Iatmul, the bands of early Chambri coalesced about 1,000 years ago and eventually formed what are now the three Chambri villages on the shores of the fishrich lake. The Chambri were contacted first by Australians in the early 1920s, and by 1924 relations between them were well established. Extensive labor migration to distant plantations began in 1927. In 1933, Mead and Reo Fortune worked for six months as anthropologists among the Chambri, and in 1959 Catholic missionaries completed construction at Indingai village of the most elaborate church in the Middle Sepik. The peoples of the Sepik River, those living along its northern and southern tributaries and those further south in the Sepik Hills, are united in a regional trading system based on interpenetrating ecological zones. This system links the Chambri with their neighbors—particularly the Mali and Bisis speakers of the Sepik Hills and the Iatmul of the Sepik River—in an exchange network that includes not only Subsistence goods but ceremonial complexes.