Gerard de Gremor, or Gerardus Mercator was born on March 5th, 1512 in Rupelmonde in Belgium, which was part of the Holy Roman Empire at the time. After studying at the University of Leuven, Mercator took the job as a craftsman of mathematical instruments.
Mercator's first job as a cartographer came in 1535, when he worked with Gemma Frisius and Gaspar Myrica to create a terrestrial globe. In this job, Mercator was not primarily a cartographer, but an engraver of brass plates used to print the maps. In 1537, Mercator began making his own maps, starting with a map of Palestine. In the following three years, Mercator published two more maps: one of the world and the other of Flanders. While learning the cartography trade, Mercator discovered the Italic script, which was useful when creating maps. After mastering the script, Mercator published the first instruction book on the Italic script in Northern Europe. In 1544, Mercator was arrested on the charges of heresy because of his sympathy for Protestant beliefs. After remaining in prison for seven months, the charges were dropped, most likely due to intervention by the university that he worked at. In 1552, Mercator moved to Duisburg, where he taught mathematics at the local university. Mercator also opened up a cartographic workshop. Mercator's first map created at this shop wasa six-panel map of Europe. Because of his skill with maps, Mercator was appointed to the position of Court Cosmographer for the Duke of Juilich-Cleves-Berg in 1564. In this position, Mercator began to construct maps that included lines of longitude and latitude so that they could be used by boats at sea.
Mercator is responsible for coining the word atlas as a collection of maps while encouraging Abraham Ortelius to compile the first modern one in 1570. Mercator made his own atlas in 1578 which contained maps made by Mercator along with those of other cartographers, including Ptoloemy. After publishing his atlas, Mercator continued to add on to it, publishing more editions until his death in 1594.
Mercator lived in Duisburg until his death on December 2nd, 1594. At the time of his death, Mercator was a wealthy and respected citizen due to his map work. Mercator made it onto our list for several reasons. First, he invented the word 'atlas'. Secondly, Mercator is also one of the first people to use the word America to describe the New World and he is definitely the first person to popularize the word America in the Old World. Being that Mercator create two commonly used words that are used in multiple languages, I'd say that Mercator was pretty important.