The Selk'nam, also known as the Onawo or Ona people, are an indigenous people in the Patagonian region of southern Argentina and Chile, including the Tierra del Fuego islands. They were one of the last native groups in South America to be encountered by migrant Europeans in the late 19th century. In the mid-19th century, there were about 4,000 Selk'nam; in 1916 Charles W. Furlong estimated there were about 800 Selk'nam living in Tierra del Fuego; with Walter Gardini stating that by 1919 there were 279, and by 1930 just over 100.

Patagonia is a geographical region that encompasses the southern end of South America, governed by Argentina and Chile. The region comprises the southern section of the Andes Mountains with lakes, fjords, temperate rainforests, and glaciers in the west and deserts, tablelands, and steppes to the east. Patagonia is bounded by the Pacific Ocean on the west, the Atlantic Ocean to the east, and many bodies of water that connect them, such as the Strait of Magellan, the Beagle Channel, and the Drake Passage to the south.