The main island was first discovered by Spaniards in 1553 by Francisco de Ulloa. In 1567 the island was conquered for Spain by Captain Martín Ruiz de Gamboa who was at the head of an expedition of 110 Spaniards. Gamboa named the islands "Nueva Galicia" (New Galicia) in honor of the place of origin of Rodrigo de Quiroga who as governor had organized the expedition. Gamboa established a settlement at Castro in 1567, which later became the seat of a Jesuit mission, and was capital of the province until the founding of Ancud in 1768.