The island of Madeira was claimed by Portuguese sailors in the service of Infante D. Henrique, Henry the Navigator in 1419, and settled after 1420. The archipelago is considered to be the first territorial discovery of the exploratory period of the Portuguese Age of Discovery. Much like the Azores, it is clear that some knowledge of Atlantic islands, such as Madeira, existed before the discovery and settlement of these lands, as the islands appear on maps as early as 1339. It would appear that the islands of Madeira had been discovered long before Portuguese vessels rediscovered them. In Libro del Conocimiento (1348–1349), a Castilian monk also identified the location of the islands in its present location, with the names Leiname (modern Italian legname, cognate of Portuguese madeira, “wood”), Diserta and Puerto Santo.