At the end of the XV and the beginning of the XVI century began the Great Geographic Discoveries. The factors that contributed to the realization of all the discoveries were many but the main ones are the changes in politics, economics (trade), and the improvements in technologies.
One of the main reasons the brought to the discovering of all the new lands was that during this period of time Europe changes politically. The monarchs reunite the power in their hands and create national countries such as England, Spain, Portugal, France, and Holland. This gives them the opportunity to create very powerful floats. Not in last place they also wanted to spread the Christian fate to the other cultures. Among these monarchs were Isabella and Ferdinand, and Prince Henry the Navigator.
Many centuries the Europeans gained silk and spices by trade with Africa, India, and China. This trade occurred on the "paths of the silk" from the Italian city Venice and the Byzantine Constantinople. Unfortunately, this way was closed when the Ottoman Turks captured Constantinople in 1453. This caused the need to find new route but this time on water. There were only to possible ways. The first one was to go south and near the west African seaside or to go west across the Atlantic Ocean. At the beginning the first one seemed more favorable. The fist European who reaches India on this route is Vasco da Gamma in 1498. By this time Columbus decided that it is possible to reach India if you go west across the Atlantic.
None of all the discoveries would have been possible if there were not any advances in the technology. During the Renaissance the Europeans started to use the gunpowder. The mapmakers begun to make new maps according to the corrections of the astrologers. With the discovery of the astrolabe, an instrument that could measure the position of the stars, the voyages became more secure. Also, the magnetic compass was improved so now the sailors could determine their location.