It is believed that the last group of uncontacted native peoples in North America were the Lacandón people, discovered in the early part of the 20th century. Both Ishi's Yahi family, and the Lacandón Maya, were aware of European colonization and the civilization that had developed from it, but purposefully avoided any direct contact, preferring to interact only with other native peoples.
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The last group of people to make contact within the environs of Mexico were the Lacandón people, thought to be a formerly urban Maya population that had retreated into the Lacandon jungle of the Yucatán Peninsula to flee Spanish colonisation. Initial contact was established in 1924, though it would be a number of decades before they fully emerged. Although some have chosen to enter mainstream culture, the remaining population in the jungle is still quite conservative regarding their contact with the outside world, and today numbers about 650 people.