Historical and ethnographic records indicate that the Piaroa have occupied much of their present territory since pre-Conquest days but also may have mixed with other populations. One hypothesis states that the extinct Adoles, who inhabited the Orinoco floodplain until they disappeared in the nineteenth century, became Piaroa after being pushed off the main river channel. The relationship between Piaroa and Mako (or Wiru) is also intimate and murky, showing close linguistic, cultural, and genealogical ties still to be sorted out by investigators. On the ethnic frontiers were Carib peoples—Yecuana, Panare, Mapoyo, Yabarana—surrounding the Piaroa on the north and east, the nomadic Guahibo and settled Saliva of the Colombian savannas on the opposite Orinoco shore, and Arawakan groups—Piapoco, Puinave, Baniwa, Bare—in the southwest Guaviare-Inírida zone. Extensive interethnic contacts involving trade, intermarriage, and cultural borrowing characterized the region in pre- and early contact times. In view of the evidence of interethnic contacts, as well as the great similarity of cultural traits regionwide, some investigators hypothesize that the middle Orinoco region, perhaps the entire Guiana region, comprised a culturally and ethnically interdependent system. By contrast, interaction between Piaroa and White society was infrequent and short-lived prior to the 1970s.
First contacts were with Jesuit missions founded along the middle Orinoco in the late seventeenth century, but the Piaroa quickly gained a reputation for being aloof and unattracted to the mission life-style. They insulated themselves deep in the forest, far upriver from the main river corridors, and avoided exposure to Whites, who they thought to be cannibals. Except for brief contacts with explorers and traders, the relative isolation of the Piaroa from White society persisted until the 1950s, when they came under the acculturative influence of a new wave of missionaries as well as agents of the Venezuelan government. Large numbers of Piaroa youth began to attend the Salesian Catholic mission school at Isla Ratón in the middle Orinoco, learning the Spanish language and White customs. Meanwhile, the North American-based New Tribes Mission converted many Piaroa to born-again evangelical Christianity. They attracted Piaroa converts to the Tamatama mission center, where they were trained as disciples before returning to their home communities to proselytize relatives and neighbors. Contemporaneous with and possibly related to these developments, epidemics of foreign diseases such as measles, malaria, and venereal disease ravaged the Piaroa population, compelling many to leave the interior in search of modern medical attention. A number of them came into contact with Dr. Hans Baumgartner (1954) and other personnel of the Malaria Service, who provided modern medicines and studied the health status of the population. Many Piaroa were thus persuaded to relocate nearer to the White centers, where Western health care was available.
Contact and acculturation to White society have intensified greatly since 1970. An estimated 80 percent of the population has converted to Christianity, and rural schools run by Piaroa teachers are found in over twenty communities. Advances in means of transportation, including roads, outboard motors, and airstrips, have given a major boost to cultural and economic integration. Regular contact with White society, including frequent trips to White towns to sell manioc flour or other cultivated or forest products and to buy Western goods, has become the norm for most Piaroa. Only 5 percent of the Piaroa—mostly those in the upper Cuao-Parguaza-Cataniapo watershed—remain largely isolated from White society and still conform to a traditional life-style.