Portugal occupies the western part of the Iberian Peninsula and is slightly smaller than Indiana. The country is crossed by three large rivers that rise in Spain, flow into the Atlantic, and divide the country into three geographic areas. The Minho River, part of the northern boundary, cuts through a mountainous area that extends south to the vicinity of the Douro River. South of the Douro, the mountains slope to the plains around the Tejo River. The remaining division is the southern one of Alentejo. The Azores stretch over 340 mi (547 km) in the Atlantic and consist of nine islands with a total area of 902 sq mi (2,335 sq km). Madeira, consisting of two inhabited islands, Madeira and Porto Santo, and two groups of uninhabited islands, lie in the Atlantic about 535 mi (861 km) southwest of Lisbon.
An early Celtic tribe, the Lusitanians, are believed to have been the first inhabitants of Portugal. The Roman Empire conquered the region in about 140 BC Toward the end of the Roman Empire, the Visigoths had invaded the entire Iberian Peninsula.
Portugal won its independence from Moorish Spain in 1143. King John I (1385–1433) unified his country at the expense of the Castilians and the Moors of Morocco. The expansion of Portugal was brilliantly coordinated by John's son, Prince Henry the Navigator. In 1488, Bartolomeu Dias reached the Cape of Good Hope, proving that Asia was accessible by sea. In 1498, Vasco da Gama reached the west coast of India. By the middle of the 16th century, the Portuguese empire extended to West and East Africa, Brazil, Persia, Indochina, and the Malayan peninsula.
In 1581, Philip II of Spain invaded Portugal and held it for 60 years, precipitating a catastrophic decline in Portuguese commerce. Courageous and shrewd explorers, the Portuguese proved to be inefficient and corrupt colonizers. By the time the Portuguese monarchy was restored in 1640, Dutch, English, and French competitors had begun to seize the lion's share of the world's colonies and commerce. Portugal retained Angola and Mozambique in Africa, and Brazil (until 1822).