Gerardus Mercator (/dʒɪˈrɑːrdəs mɜːrˈkeɪtər/;[1][2][3] 5 March 1512 – 2 December 1594)[4] was a 16th-century geographer, cosmographer and cartographer from Flanders. He is most renowned for creating the 1569 world map based on a new projection which represented sailing courses of constant bearing (rhumb lines) as straight lines—an innovation that is still employed in nautical charts.
Mercator was one of the pioneers of cartography and is widely considered the most notable figure of the school in its golden age (approximately 1570s–1670s). In his own day, he was a notable as maker of globes and scientific instruments. In addition, he had interests in theology, philosophy, history, mathematics and geomagnetism. He was also an accomplished engraver and calligrapher. Unlike other great scholars of the age he travelled little and his knowledge of geography came from his library of over one thousand books and maps, from his visitors and from his vast correspondence (in six languages) with other scholars, statesmen, travellers, merchants and seamen. Mercator's early maps were in large formats suitable for wall mounting but in the second half of his life, he produced over 100 new regional maps in a smaller format suitable for binding into his Atlas of 1595. This was the first appearance of the word Atlas in reference to a book of maps. However, Mercator used it as a neologism for a treatise (Cosmologia) on the creation, history and description of the universe, not simply a collection of maps. He chose the word as a commemoration of the Titan Atlas, "King of Mauretania", whom he considered to be the first great geographer.
