The most important contribution to European expansion was the search for new trade routes. Christopher Columbus in 1492 accidentally stumbled across the Americas on his way to India in search of foreign goods and a new, quicker path to get to them. The Europeans already had trade routes, but each of them had a flaw. Either the route was too long, too costly, or too long. The main countries of their times sent different explorer's to find new trade routes.
Portuguese Prince Henry (the Navigator) founded an observatory and navigation school on the southern Portuguese coast at Sagres. He basically directed Portguese exploration during his lifetime. After this death exploration was directed by a private "contractor" named Fernao Gomes. Bartholomew Dias reached the Cape of Good Hope at the south end of Africa in 1487 and returned to Portugal with the news. Vasco da Gama reached the Swahili Coast of East Africa on his way to India.
He returned to Portugal with spices from India. In 1494, the Spanish and the Portuguese signed a treaty to divide the world in two. The dividing line ran through the Atlantic with Spain gaining lands to the west including all the Americas. Brazil was given to Portugal. The eastern half including Africa and India was given to Portugal as well.
The Spanish country came into great unity after the marriage of Ferdinand of Argon and Isabelle Castile. In 1492 Columbus led three ships from Cadiz in search of a trade route to India instead he found the Bahamas. He had basically discovered a new world. Vasco Nunez de Balboa, sailing for Spain, reached the Pacific Ocean in Panama in 1513, claiming everything touched by the Pacific Ocean for the king. Ferdinand Magellan led a Spanish expedition that sailed around the world. Although...