The Hispanic and Latino presence in the US predates the existence of the US itself. Spanish exploration and colonization of North, Central, and South America in the sixteenth century began with the establishment of colonies in Puerto Rico in 1509. Florida, Texas, California, and the Southwest were regions of intense Spanish and (in Texas and further west) Mexican exploration, colonization, and cultivation throughout the sixteenth, seventeenth, and eighteenth centuries. As recently as 160 years ago, Texas was still part of Mexico; California and the entire Southwest comprised northernmost Mexico until 1848, when the Treaty of Guadalupe Hidalgo ended hostilities in the Mexican American war. In that war, Mexico lost nearly half its territory, and that treaty guaranteed both US citizenship and retention of property rights to Mexicans living in the territory ceded to the US. As it worked out, however, many Mexican American landowners were dispossessed of their lands soon after the war and had to face other forms of discrimination. A generation later, the Mexican revolution (1910- 21) prompted emigration to the US, a flow that continues to the present day.