History of Portugal (1640–1777) put to the test in 1762 when Spain invaded aided by France, during the Seven Years' War. Britain invoked its alliance with Portugal and sent troops. Several months later, the conflict was settled with comparatively little fighting. In 1777, Spain and Portugal signed the Treaty of San Ildefonso, which mainly resolved a number of border disputes between their South American colonies. During the Age of Enlightenment, Portugal was considered one of Europe's unenlightened backwaters; it was a country of three million with 200,000 people in 538 monasteries in 1750. Melo seems to have been deeply embarrassed by Portugal's much lamented
History of Portugal 2014. Later Neanderthals roamed the northern Iberian peninsula and a tooth has been found at Nova da Columbeira cave in Estremadura. Homo sapiens sapiens arrived in Portugal around 35,000 years ago and spread rapidly throughout the country. Pre-Celtic tribes inhabited Portugal leaving a remarkable cultural footprint. The Cynetes developed a written language, leaving many stelae, which are mainly found in the south of Portugal. Early in the first millennium BC, several waves of Celts invaded Portugal from Central Europe and intermarried with the local populations to form several different ethnic groups, with many tribes. The Celtic presence in Portugal is