Which Flemish cartographer created the Mercator projection world map in 1569?

Gerardus Mercator created the world map of 1569 that introduced the projection now known as the Mercator projection.

The map’s Latin title described it as a new and more complete representation of the Earth adapted for navigation. Its key innovation was representing rhumb lines—routes sailed at a constant compass bearing—as straight lines. That made the chart especially useful to mariners planning courses across the globe.

Mercator’s projection preserves local angles and shapes, but it greatly enlarges areas toward the poles. Greenland, for example, appears far larger than it really is compared with Africa. The distortion becomes infinite at the poles, so the map cannot show them directly in its normal form.

The 1569 world map was a large planisphere printed from eighteen copper-engraved sheets, measuring about 202 by 124 centimeters when assembled. Mercator was Flemish and worked as a geographer, cartographer, and instrument maker. Abraham Ortelius was another major Flemish cartographer, but Mercator—not Ortelius—created this projection-defining map.