Magellan offered to prove that the East Indies fell unde r Spanish authority. On September 20, 1519, Magellan set sail from Spain with five ships. More than a year later,
one of these ships was exploring the topography of South America in search of a water route across the
continent. This ship sank, but the remaining four ships searched along the southern peninsula of South
America. Finally they found the passage they sought near a latitude of 50 degreesS. Magellan named this
passage the Straitof AllSaints, but today we know it as the Strait of Magellan.