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June 2016-The Map Maker of the American West

June 2016-The Map Maker of the American West

The Map Maker of the American West

Gouverneur Kemble Warren was at the right place at the right time and made the right decision.

Warren was chief engineer of the Army of the Potomac during the American Civil War. During the Battle of Gettysburg, on July 1-3, 1863, he climbed Little Round Top, the second highest elevation on the battlefield. He found it unoccupied except for a small Signal Corps detachment. He immediately ordered Union troops to seize Little Round Top. They arrived just in time to hold off a Confederate attack. As a result, the Union army was able to hold this key position and go on to win the battle.

Years earlier, Warren had also been at the right place at the right time making the right decisions.

Graham A. Callaway and W. Raymond Wood called Warren “the single most important cartographer of the American West” in their introduction to “Lieutenant G.K. Warren’s 1855 and 1856 Manuscript Maps of the Missouri River.” At the time, Warren was a lieutenant in the U.S. Army Corps of Topographical Engineers.

Warren is credited with making the first reliable maps of the Black Hills and adjacent region, and with creating the first comprehensive map of the United States west of the Mississippi River. His reports are among the most readable and instructive official documents published by the government, and provide scientific knowledge of the region prior to white settlement, according to Callaway and Wood.

Born on Jan. 8, 1830 at Cold Spring, N.Y., Warren was named for his father’s friend Gouverneur Kemble, a U.S. Congressman, diplomat and industrialist from New York. Warren received an appointment to the United States Military Academy at West Point when he was 16 and graduated second in his class in 1850.

In 1855, Warren was the topographical engineer for an expedition led by Gen. William S. Harney that took him from Fort Pierre to Fort Kearny in Nebraska across the Nebraska Sand Hills, then through the Badlands in what is now South Dakota.

Warren returned west the next year to survey the Missouri River from the southern boundary of Nebraska to a point 60 miles above the mouth of the Yellowstone.

“Lieutenant G.K. Warren’s 1855 and 1856 Manuscript Maps of the Missouri River” contains charts of the river from the northern boundary of Kansas to a point above Fort Union, in what is now North Dakota. The charts are significant not only because they are among the earliest detailed maps of the Missouri River but because they contain symbols denoting sand bars, trees, bluff lines, tributary streams and other features. The maps show how the course of the river has changed and where villages, forts and towns were located. Copies of the map were published by the State Historical Society of North Dakota, and are sold in the Heritage Store at the Cultural Heritage Center in Pierre. The map can be purchased at the website or by calling (605) 773-6346.

In 1857, Warren obtained further data on the Central Plains from an exploration that skirted the Black Hills and the Niobrara and Loup rivers in Nebraska.

The government published a report of the three western expeditions as the “Preliminary Report of Explorations in Nebraska and Dakota, in the Years 1855 –’56 – ’57.”

The reports included information about rivers, routes, transportation, American Indians, military posts and meteorological observations.

Warren visited what is now South Dakota during a drought, and wrote that “continuous settlements cannot be made in Nebraska, west of the 97th meridian, both on account of the unfavorable climate and want of fertility in the soil.”

At the start of the Civil War, Warren was a mathematics instructor at West Point. He was appointed lieutenant colonel of the 5th New York Infantry on May 14, 1861.

was called the “hero of Little Round Top” for his actions on July 2, 1863, and promoted to major general. At the Battle of the Five Forks on April 1, 1865, Maj. Gen. Philip Sheridan judged that troops under Warren’s command had moved too slowly and relieved Warren of command on the spot.

Warren returned to work for the Corps of Topographical Engineers after the Civil War and became the first district engineer of the St. Paul District in 1866. One of his first tasks was to study potential sites for railroad bridge construction across the Mississippi River between St. Paul and St. Louis.

During this time, Warren requested a military court of inquiry to clear his name. The court of inquiry was denied until 1879. The court found that Sheridan had not been justified in relieving Warren of his command, but it was too late for Warren to find comfort in the ruling. He died on Aug. 8, 1882, three months before court findings were published.

Several statues of Warren commemorate his service in the Civil War, including one at Little Round Top.
The photo of the U.S.S. South Dakota is courtesy of the State Archives.

This moment in South Dakota history is provided by the South Dakota Historical Society Foundation, the nonprofit fundraising partner of the South Dakota State Historical Society at the Cultural Heritage Center in Pierre. Find us on the web at Contact us at to submit a story idea.