Stephen H. Long.
Stephen Harriman Long was an engineer, explorer, and military officer; Long led what’s known as Long’s Expedition through the Great Plains. He was born at Hopkinton, New Hampshire, on December 30, 1784, a son of Moses and Lucy (Harriman) Long. He graduated from Dartmouth College in 1809 with a bachelor’s degree, then continued his education at the same institution and earned a master’s degree in 1812. Two years later, he was commissioned as a lieutenant of engineers in the United States Army and, from 1815 to 1818, served as a mathematics professor in the military academy at West Point.
In April 1819, he was promoted to brevet major and appointed to lead an expedition to explore the territory between the Mississippi River and the Rocky Mountains. Just a month before receiving this appointment, he married Martha Hodgkins of Philadelphia, Pennsylvania, on March 3, 1819. After returning from the expedition, he spent several years surveying and building the Baltimore & Ohio and other railroads. He also became an inventor and received several patents for steam locomotives. When the United States Topographical Engineers’ Corps was organized in 1838, Major Long was given an important position in the corps. After several years of service in this corps, he retired from the army and died at Alton, Illinois, on September 4, 1864.
© Kathy Alexander/Legends of America, updated October 2026.
Also See:
Soldiers & Officers in American History
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