William H. Cosgrove was born in 1843 in Jackson County, Missouri. He traveled extensively in the West and lived in Santa Fe, New Mexico from 1874-1878. In 1878, he moved to a ranch on the site of present-day Roswell. His brother had a contract to carry mail from Las Vegas, New Mexico to Mesilla, New Mexico by way of Fort Stanton, and Cosgrove assisted him with this route. In time, Cosgrove established a mercantile store in Roswell in partnership with John W. Poe and J.S. Lea. The partners sold the store in 1892, and Cosgrove became postmaster and Receiver of Public Monies in the Roswell Land Office in 1893.
From the description of William H. Cosgrove papers, 1883-1933. (New Mexico State University). WorldCat record id: 68908623
