Amahuaca formerly occupied a vast area east of the Ucayali River from the Tapiche River south to the Urubamba. Repeatedly raided by Panoan Conibo, Shetebo, and Shipibo, as well as Arawakan Piro in the seventeenth through nineteenth centuries, the Amahuaca withdrew eastward to the higher land. In the 1890s prospectors entered that area with thousands of Piro and Campa helpers, seeking workers to collect rubber. When the Amahuaca resisted, many were killed and many others died of introduced diseases. Survivors fled further east down the Purus River but soon returned to headwater streams to escape advancing Brazilians. In the 1940s a few joined logging crews on the upper Ucayali River, where they formed a village on Chumichinia Island. Between 1953 and 1968 a Protestant missionary attracted some seventeen families to Varadero, the site of an old rubber camp later occupied by a Peruvian army garrison. About the same time Dominican missionaries also attracted some families to the lower Sepahua River.
The description that follows is of the traditional upland culture. Amahuaca culture is most similar to that of the Yaminahua, Shimanahua, Matses, Matis, and Marubo. It is also more similar to that of the Cashinahua than to that of the riverine Conibo-Shipibo. As part of recent changes, Amahuaca in the riverine communities, especially those on Chumichinia, have borrowed ceramic and basketry design, cloth mosquito nets, strongly alcoholic manioc beer, and some oral lore from nearby Conibo and Campa. Houses, some of which have closed walls, tend to be arranged along the water's edge. People sleep under box-shaped nets on the raised floors instead of in hammocks. Secondary forest that may be inundated annually is cleared for maize and bananas near the dwellings, whereas manioc may be planted in a separate area that does not flood. These crops and numerous fruit and vegetable crops that the Amahuaca have adopted from Peruvians and missionaries are weeded. Dugout canoes are widely used, and fish, by far the most abundant source of protein at Chumichinia, are caught with harpoon arrows, spears, poison, and hooks, as well as with bows and ordinary arrows, which are no longer carried all the time for defense. A few men have taken Conibo or Campa wives and cooperate with their wives' groups in poisoning fish. Some men work in a system of debt peonage, receiving metal tools, utensils, weapons, fuel, clothes and cloth, soap, outboard motors, and processed food on credit from their patron. To pay off their debt they cut cedar and mahogany logs on eastern tributaries of the Ucayali during the dry season and float them as rafts down to the Ucayali when rains swell the rivers. Riverine Amahuaca occasionally supply cured pelts, young game mammals, birds, surplus fish, bananas, maize, and tobacco to river merchants, missionaries, and lumber patrones for cash to purchase manufactured goods. Traditional ornaments and art have been abandoned, and all the Amahuaca wear commercial clothes. Children, especially boys, attend school for a few years and bilingualism is common. Although one man is favored by a lumber patrón as mediator-leader, all the men make policy decisions jointly. Harvest ceremonies have lapsed and the hallucinogen ayahuasca is rarely used. Instead relatives frequently gather during slack periods to drink manioc beer. Some Christian concepts and practices have been adopted, including simple burial.