The borders of the United States have expanded considerably since independence was declared. As the nation grew, newer and more detailed maps were needed so the country could plan ahead and use the landscape and resources available. Gen. William Emory, an Army cartographer, was a vital part of this process. Emory’s diligent studies and attention to detail not only shaped the borders of the United States but also shaped the borders of Texas and revealed the great wonders of the Upper Rio Grande.

William Hemsley Emory was born in September 1811 in Eastern Maryland. He was extremely bright and as a young man earned an appointment to the United States Military Academy at West Point, New York. 

He graduated from West Point in 1831 as a lieutenant and was assigned to an artillery unit. Looking for other opportunities to satisfy his curiosity and imagination, he resigned from the service in 1836 to pursue civil engineering. The Army, however, lured him back two years later with a unique new program, the Corps of Topographical Engineers. This new unit was in charge of surveying resources and infrastructure for both potential military use and civilian development. He spent the next few years engaged in careful surveys of harbors and rivers on the East Coast. Also in 1838, he married Matilda Bache in Philadelphia. Bache was the great-granddaughter of Benjamin Franklin and the daughter of later Texas State Sen. Richard Bache Jr.

In 1844, Emory arrived in Texas. Though Texas was still independent, its government was working with the United States in pursuit of annexation and invited the Corps of Topographical Engineers into the republic to examine what Texas had to offer. He spent months studying the Upper Rio Grande Valley, producing maps that were invaluable to American forces during the Mexican War two years later and much more accurate than had been produced up to that point. His surveys of the American-Canadian border between 1844 and 1846 were also a valuable part of the negotiations over the resolution of the Oregon Country dispute and helped finalize the border between the two nations.

When war erupted against Mexico in 1846, he was assigned to join Col. Stephen Kearney in his trek from Kansas to New Mexico and then to California to strip the lightly populated and almost undefended area away from Mexico. The mission was a tremendous success, and the northern third of Mexico was in American hands in a matter of months. Along the way, Emory continued to make careful surveys and notes of the regions the army marched through. In the course of the war, Mexican troops never again entered Texas. When the war was won in 1848, the Texas border at the Rio Grande was unquestioned, thanks to Emory’s maps.

His efforts would reap huge dividends again in 1853 when the United States finalized the Gadsden Purchase from Mexico. The United States had won what is now the southwestern quarter of the country as a result of the Treaty of Guadalupe-Hidalgo in 1848. Mexico surrendered the lands from the Rio Grande in central New Mexico (what was then West Texas) across to California and the Pacific. Because of Emory’s surveys, federal officials realized some of the unique features of the area. Just south of the Gila River was a break in the Rocky Mountains, an area where the land was relatively smooth. The area was ideal for railroad construction as the concept and ultimate route of the transcontinental railroad began to be discussed. As a result, Ambassador James Gadsden negotiated a new treaty with Mexico, paying $10 million for the land that became the southern edges of Arizona and New Mexico. Emory’s correspondence with U.S. Sen. Thomas Rusk of Texas helped secure the treaty ratification in the Senate.

In 1855, Emory was named head of the International Boundary Commission. His reputation as a scientist and a mapmaker was growing. His two major reports on the geography and wildlife of the Southwest, “Notes of a Military Reconnaissance from Fort Leavenworth to San Diego” (1846) and “Report of the United States and Mexico Boundary Commission” (1859) were major foundations in the later scientific study of the area.

During the Civil War, Emory served with distinction, rising to the rank of general and taking command of the Nineteenth Corps during the Shenandoah Campaign of 1864. He commanded the Department of the Gulf during Reconstruction, which served in Louisiana, Arkansas and Mississippi. In 1874, as the terroristic White League overthrew the elected government of Louisiana, Emory resorted to diplomacy to convince the coup plotters to restore the elected government and to peacefully disband. What could easily have escalated ended without further bloodshed.

He retired from the Army in 1876 and moved east. He died in Washington, D.C. in 1887 at age 76. Emory continued to be widely respected by geographers and cartographers in the years after his passing. Emory Peak in the Big Bend area was named in his honor as well as New Mexico’s Emory Pass. Astronauts also named a crater on the Moon after him during the 1972 Apollo 17 mission. In the end, his years of study and calculations had an impact that shaped the United States and touched the heavens.

Ken Bridges is a historian, writer and native Texan. Reach him at drkenbridges@gmail.com.

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