The French explorer Jacques Cartier was the first European to discover Anticosti Island, in 1534. He originally named it Isle d'Assomption, as well as declaring it a strange and cursed island. However, by the 17th century it was referred to as Anticosti, in an attempt to mimic the name used by the indigenous people of the area.
Although historically more of a hunting ground than anything else, the island was settled in 1680, when King Louis XIV of France handed it over to the explorer Louis Jolliet. Jolliet, finding himself in possession of the largest privately-owned island in the world, built a fort for his family there. Despite its size, Anticosti has never been a well-populated island, likely due to its treacherous coastline.
(Fun fact: Over 400 ships wrecked themselves on the rocks and reefs surrounding the island, earning it the nickname "The Cemetery of the Gulf". –V.)
Anticosti became a territory of the British Empire as part of the Treaty of Paris that ended the Seven Years War, and officially became part of the province of Quebec in 1867.