sentences:  Colonialism in the modern sense began with the "Age of Discovery", led by Portuguese, and then by the Spanish exploration of the Americas, the coasts of Africa, the Middle East, India and East Asia.The Portuguese and Spanish empires were the first global empires because they were the first to stretch across different continents, covering vast territories around the globe.Between 1580 and 1640, the two empires were both ruled by the Spanish monarchs in personal union.