Which friar discovered the Manila galleons' return route across the Pacific?

Andrés de Urdaneta discovered the return route that made the Manila galleon system possible.

In 1565, the Augustinian friar and experienced navigator sailed from Cebu aboard the San Pedro with Felipe de Salcedo. Instead of attempting a direct eastward crossing through the tropics, Urdaneta steered north toward the Pacific’s prevailing westerly winds and the Kuroshio Current. Those forces carried the ship toward the coast of North America, from which it continued south to Acapulco.

The voyage reached Acapulco on October 8, 1565, after roughly four months at sea. Urdaneta’s detailed observations made the route repeatable, allowing Spanish ships to maintain a regular connection between the Philippines and New Spain for about 250 years.

A common mix-up is Alonso de Arellano, whose small vessel reached New Spain slightly earlier in 1565. However, Urdaneta is conventionally credited because he documented a reliable route and explained its navigational logic. The route is known as the tornaviaje, or “return voyage.”