The Iberian Peninsula is a geographic unit that contains a number of distinct regions based on climate and geomorphology, such as Andalusia, Castile, Galicia, and Lusitania. Lusitania, which now encompasses the modern nation-state of Portugal, is generally set off from the other regions of the peninsula by areas of higher elevation that run parallel to the Atlantic coast, greater rainfall, and a more moderate climate. It was this regional distinctiveness, as well as the internal geography of Lusitania--largely open to the south but hemmed in by mountains on the east and the Atlantic Ocean on the west--that gave rise to a culturally and socially distinct people, the Portuguese, and later to an independent nation-state, Portugal.
Data as of January 1993