From 1100 to 1900, Jicarilla Apache, Ute, Comanche, Pueblo, and other Native Americans hunted prairie game, harvested seasonal wild plants, and used the rivers, mountains, and valleys to define the boundaries of their world; descendants in the American Southwest still consider this their ancestral homeland. From the 1600s into the early 1900s, Spanish and then Mexican ranchers grazed sheep and cultivated the land through grants awarded to individuals or communities, and Fort Union National Monument lies within the historic Mora Land Grant. From 1821 to 1880, traders followed pathways first used by Native Americans and trappers and carved the Santa Fe Trail into the landscape. From 1846 to 1891, after the war with Mexico, the U.S. military established posts such as Fort Union to protect the U.S. Territory of New Mexico. From 1880 to the present, the Atchison, Topeka, and Santa Fe Railroad replaced the Santa Fe Trail and permanently changed transportation and commerce in the southwestern U.S. Ranching on the high plains, beginning with Spanish settlers, continues today.