Gerard Mercator was born in 1512 in the Flemish town of Rupelmonde, and he died in 1594 in Duisburg/Germany. Still in the Spanish Netherlands, he prepared astronomical tools, Globes, the Chart of Palestine and Flanders, his World Map of 1538, and a treatise on the use of italics on charts. In 1544, he was suspected of heretical thoughts and spent some time in jail in Rupelmonde, but was released that same year. Eight years later, he settled in Duisburg, a town in the Duchy of Julich-Kleve-Berg, perhaps to teach at the university, as the Duke had in mind.

In 1538, Mercator published a 14 by 21 inch (36 by 55 cm) world map, laid out on the double cordiform (double heart-shaped) projection, which was pioneered in 1531 by the French mathematician Oronce Finé. Mercator’s following publication was a detailed 34 by 46 inch (87 by 117 cm) map of Flanders, printed as four sheets in 1540. Prepared at the urging of Flemish merchants, the map was based on precise trigonometric and field surveys.

• Maps by Mercator for sale