We know of many explorers and travelers from the Middle East, Africa, and China before the 1400s. But during the fifteenth century, advances in exploration occurred in a relative backwater of the world, western Europe.
At the dawn of the 1400s, most Europeans tilled the soil and had little knowledge of the world beyond their villages. The coasts of Africa were uncharted. The continents of North and South America were unknown to Europeans.
China, Japan, and India were mysterious lands described in legend and song. Except for generations of secretive fishermen, sailors dared not venture into the dark and unmapped seas, where many people believed that monsters lurked and the sea boiled.
But over a period of 100 years, from about 1450 to 1550, a handful of European explorers would encounter and chart much of the world, the coasts of Africa and Asia, North America, South America, and the vast Pacific Ocean, dotted with islands.
The medieval map was replaced with the globe inscribed with the rough outlines of the continents.