About a thousand years ago, and for hundreds of thousands of years before that, most of the world was made up of hunter-gatherer tribes. Civilization only existed in Europe, north Africa, and Asia -- the rest of the world was unknown. This included most of Africa, Southeast Asia, Oceania, Australia, and the Americas. After the Age of Exploration in the 15th, 16th, and early 17th centuries, much of the world had been discovered (then subjugated) by Europeans, primarily excepting Australia, Oceania, the heart of Africa, and scattered spots in the Americas.
Today, in the early 21st century, one might think that all the world's people are now part of civilization or at least directly exposed to it frequently. This is almost true, but not quite. There are still the rare phenomenon of the uncontacted tribe -- the tribe that has had barely any, if any, interaction with global civilization. These "wild humans" lead Stone Age lives, living in the world's most isolated places like the Amazon, New Guinea, and a small island in the Bay of Bengal. These untouched peoples are an example of what human life was like before the rise of civilization. They are usually almost entirely unclothed, and hunt using spears or bows and arrows. Many of them use elaborate face paint and have shamanistic religions.
For a couple centuries, Australia was the center of the uncontacted tribe, as the continent was not settled by Europeans until the late 18th century, the last habitable continent to be so colonized. Aborigines, who represent one of the earliest offshoots of humanity outside of Africa, have lived there for about 50,000 years. In 1984, the land aborigines living a traditional hunter-gatherer lifestyle, an uncontacted tribe known as the Pintupi Nine, which were located by "aboriginal trackers" and brought to Kintore, Northern Territory. They were immediately embarrassed by their nakedness, putting on clothes, an experience they found terribly uncomfortable. They expressed amazement at the abundance of available food and water in the community. It is believed that the Pintupi Nine were the last uncontacted tribe in Australia.
Today, most uncontacted tribes live scattered throughout the Amazon, where the thickness and danger of the forest has isolated them from interaction civilization. These Amazon tribes are often extremely aggressive, given the status of "uncontacted tribe" in part due to their extreme hostility to any attempts at contact. On a few occasions, uncontacted tribes have been observed shooting arrows at planes that rarely pass overhead. Brazil alone has 67 known uncontacted tribes. The isolation and safety of these tribes has been put at risk from excessive deforestation of the rainforest and conflicts with loggers.