Vasco Núñez de Balboa
Vasco Núñez de Balboa (; c. 1475around January 12–21, 1519) was a Spanish explorer, governor, and conquistador. He is best known for having crossed the Isthmus of Panama to the Pacific Ocean in 1513, becoming the first European to lead an expedition to have seen or reached the Pacific from the New World.
Territorial evolution of North America prior to 1763
The claims of Spain on the Pacific coast dated to the papal bull of 1493 which had granted to Spain the rights to colonize the western coast of North America and to the actions of Vasco Núñez de Balboa in 1513, when he claimed all the "South Sea" (the Pacific Ocean) and the lands adjoining the Pacific Ocean for the Spanish Crown.