The First Battle of Acentejo took place on the island of Tenerife between the Guanches and an alliance of Spaniards, other Europeans, and associated natives (mostly from other islands), on May 31, 1494, during the Spanish conquest of this island. It resulted in a victory for the Guanches of Tenerife. A town built on the site where the battle occurred is called La Matanza de Acentejo ("The Slaughter of Acentejo"), which also contains a large mural commemorating the victory. This was the greatest defeat in the history of the Spanish Atlantic expansion, in terms of casualties suffered by Spain.