<P> Following the end of the Mexican--American War in 1848, the U.S. Army made military surveys of the uncharted land of the Big Bend . Forts and outposts were established across Trans - Pecos Texas to protect migrating settlers from Indian attacks . A significant proportion of the soldiers in the late 1800s were African American and came to be called the "buffalo soldiers", a name apparently given to them by the Native Americans . Lieutenant Henry Flipper, the first American of African ancestry to graduate from West Point, served in Shafter, Texas, near the end of the 19th century . (Shafter, named for General William R. Shafter, lies west of the Big Bend along the highway from Presidio to Marfa .) Ranchers began to settle in the Big Bend about 1880, and by 1900, sheep, goat, and cattle ranches occupied most of the area . The delicate desert environment was soon overgrazed . </P> <P> In the late 19th and early 20th century, valuable mineral deposits were discovered and brought settlers who worked in the mines or supported the mines by farming or by cutting timber for the mines and smelters . Communities sprang up around the mines . Boquillas and Terlingua both resulted from mining operations . During this period, the Rio Grande flood plain was settled by farmers . Settlements developed with names like Terlingua Abajo, San Vicente, La Coyota, and Castolon . Often, no more than clusters of families were living and farming in the same area, and they were successful only to the degree that the land was able to support them . </P> <P> In the 1930s, many people who loved the Big Bend country saw that it was a land of unique contrast and beauty that was worth preserving for future generations . In 1933, the Texas Legislature passed legislation to establish Texas Canyons State Park . Later that year, the park was redesignated Big Bend State Park . In 1935, the United States Congress passed legislation that would enable the acquisition of the land for a national park . The State of Texas deeded the land that it had acquired to the federal government, and on June 12, 1944, Big Bend National Park became a reality . The park opened to visitors on July 1, 1944 . </P> <P> Despite its harsh desert environment, Big Bend has more than 1,200 species of plants (including 60 cactus species), over 600 species of vertebrates, and about 3,600 insect species . The variety of life is largely due to the diverse ecology and changes in elevation between the dry, hot desert, the cool mountains, and the fertile river valley . </P>

Which number indicates the region in which big bend national park is located