The history of Alaska ates back to the end of the Upper Paleolithic Period (around 12,000 BC), when Asiatic groups crossed the Bering Land Bridge into what is now western Alaska. At the time of European contact by the Russian explorers, the area was populated by Alaska Native groups. The name "Alaska" derives from the Aleut word alaxsxaq, (an Archaic spelling being alyeska), meaning "mainland" (literally, "the object toward which the action of the sea is directed").