Hispanic Heritage Month (September 15–October 15) in the United States is the period when people recognize the contributions of Hispanic Americans to the United States and to celebrate Hispanic Cultural heritage and Hispanic culture. Hispanic Heritage Week was approved by President Lyndon Johnson and was expanded by President Ronald Reagan in 1988 to cover a 31-day period. It was enacted into law on August 17, 1988 on the approval of Public Law 100-402.
"September 15 was chosen as the starting point for the celebration because it is the anniversary of independence of five Latin American countries: Costa Rica, El Salvador, Guatemala, Honduras and Nicaragua. They all declared independence in 1821. In addition, Mexico, Chile and Belize celebrate their independence days on September 16, September 18, and September 21, respectively." 
Hispanic Heritage Month also celebrates the long and important presence of Hispanic Americans in North America. A map of late 18th century North America shows this presence, from the small outpost of San Francisco founded in the desolate wilderness of Alta California in 1776, through the Spanish province of Texas with its vaqueros (cowboys), to the fortress of St. Augustine, Florida -- the first continuous European settlement in North America founded in 1565, decades before Jamestown, Virginia.
Spanish explorers traveled further north along the Pacific Coast to Canada in 1774 and by the late 18th century had established a military post on Vancouver Island, 350 miles north of Seattle. The Spanish sailed up the Atlantic Coast through the Chesapeake Bay in 1526, then called the Bahía de Santa María, about 80 years before the romanticized English encounter with Pocahontas. In the 1520s Spanish navigators also explored as far north as Cape Cod, Massachusetts, and the present site of Bangor, Maine. The Spanish settled the southwest of North America in the 16th century and officially founded Santa Fe, New Mexico in 1610.
As part of the Treaty of Paris (1763) peace settlement of the French and Indian War, the territories west of the Mississippi River, including Louisiana and New Orleans, were ceded to the Spanish. Nearly all of the surviving 18th century architecture of the Vieux Carré French Quarter dates from this Spanish period.