Exploration
In the Pacific Ocean, Jorge de Menezes (c. 1498–?), discovered Papua New Guinea. García Jofre de Loaísa (1490–1526), discovered the Marshall Islands. Explorations of the Americas began with the initial discovery of America by Christopher Columbus (1451–1506), who led a Castilian (Spanish) expedition across the Atlantic, discovering America. After the discovery of America by Columbus, a number of important expeditions were sent out to explore the Western Hemisphere. This included Juan Ponce de León (1474–1521), who discovered and mapped the coast of Florida; Vasco Núñez de Balboa (c. 1475–1519), who was the first European to view the Pacific Ocean from American shores (after crossing the Isthmus of Panama) confirming that America was a separate continent from Asia; Aleixo Garcia (14?–1527), who explored the territories of present-day southern Brazil, Paraguay and Bolivia, crossing the Chaco and reaching the Andes (near Sucre).
United States
In 1507, the German cartographer Martin Waldseemüller produced a world map on which he named the lands of the Western Hemisphere "America" in honor of the Italian explorer and cartographer Amerigo Vespucci (). The first documentary evidence of the phrase "United States of America" is from a letter dated January 2, 1776, written by Stephen Moylan, Esq., to George Washington's aide-de-camp and Muster-Master General of the Continental Army, Lt. Col. Joseph Reed. Moylan expressed his wish to go "with full and ample powers from the United States of America to Spain" to seek assistance in the revolutionary war effort. The first known publication of the phrase "United States of America" was in an anonymous essay in "The Virginia Gazette" newspaper in Williamsburg, Virginia, on April 6, 1776.