The Korubo Indians are the most recent previously uncontacted Amazonian tribe to be contacted. The Korubos are said to have been initially discovered by the outside world in the year 1996. Subsequently, the Korubo tribe became known as the Caceteiros by the local people in Brazil. The word caceteiro means "club-wielders" in Portuguese and refers to their carrying clubs as weapons to defend themselves. However, newspaper reporters began calling them the "Head-Bashers" and this might be due to a mistranslation by a French anthropologist of the Portuguese word caceteiro which is similar to the French word casse-tête which literally means "break-head." Until relatively recently, the use of war clubs by indigenous people was not uncommon in the Amazon, and the men in the Shipibo tribe only stopped carrying clubs within the last generation. 
The word "Korubo" comes from the Matis tribe and means "dirty-feet" in their language. The auto-denomination term that the Korubos use to call themselves is the Dslala. The Dslala people speak a Northern Pano dialect in the Pano language family. Dslala or Korubo is mutually intelligible with Matis. For many years before the first peaceful contact with the Korubo, it was unknown as to what language they speak. Consequently, the first expeditions by the Brazilian government to make peaceful contact with the Korubo included interpreters from all the various tribes of the Javari River Valley (Vale do Javari) including the Matis, Mayoruna-Matses, Marubo, Kanamari, and Kulina. The language of the Korubos turned out to be quite close to the Matis. In fact, the Korubo share many other traits with the Matis, including the use of blowguns to hunt. However, the Korubo are different from the Matis in other ways, especially physically, being heavier and stouter than the Matis who are typically very slender. Additionally, the Korubo sport a very different hair style, shaving or cutting very short the hair on the rear of the head. Another different in physical appearance is the absence of facial tattoos which the other tribes in the area (Matis, Mayoruna-Matses, and Marubo) all have.
Although the first peaceful contact with the Korubo occurred in 1996, the Brazilian government has known about them for many years. In the book, Polvos Indígenas no Brasil, Javari, Volume 5 (Indigenous People of Brazil, Javari, Volume 5) published by the Brazilian government, the Korubos are referred to simply as the "Indios da confluência do Ituí com o Itacoaí" (Indians from the confluence of the Itui and Itaquai Rivers). The book dedicates a chapter to the Korubo, showing photographs of them taken from passing boats and reviews their history of contact with the outside world. According to the book, in 1928 a group composed of a Brazilian, a Peruvian, and five members of the Ticuna tribe encountered the Korubos and a battle followed during which over forty Korubos were shot and killed. The Korubos were reported to have used spears and clubs as weapons, lacking the use of bows and arrows. Subsequent violent encounters with the Korubos occurred and records of the Policia Federal (Federal Police of Brazil) report at least 33 fatalities of Brazilians due to fatal encounters with the Korubos. Permanent contact with the Korubo did not occur until the Brazilian government agency FUNAI (Fundação Nacional do Índio), whose mission it is to protect the rights of indigenous people, decided to install a permanent post at the confluence of the Itui and Itaquai Rivers in 1996. The function of the post was to prevent non-indigenous people from entering the new reserve that was recently created for the various tribes that live in the region. Subsequently, a small group of twenty-three Korubos, made contact with FUNAI personnel at the post. This group of Korubos is a splinter group of the main group of Korubos which is estimated to number 150 individuals. Perhaps not surprisingly, considering the history of how the Korubos have defended their lands, subsequent violent encounters with the FUNAI occurred, and seven of their agents perished.
More recently, relations with this band of Korubos improved. In fact, they were featured in a Discovery Channel documentary and National Geographic and Smithsonian Magazine articles. Paradoxically, the FUNAI has allowed access to the Korubo tribe by the media and journalists, but has denied access to them by anthropologists. Therefore, scientists know very little about the Korubo. One would think that the FUNAI would want to learn more about the culture of these indigenous Amazonians so that they could better care for them. Allowing selected members of the press access to the Korubos is an obvious attempt by FUNAI officials to shed their governmental agency in favorable light. Their strategy has seemed to have worked and there is little international criticism of their policies and management of indigenous people in the Javari Valley. Recently, the FUNAI has been arming the Korubos with shotguns in order to defend themselves.
