Coleman is a small unincorporated community in Johnston County, Oklahoma, United States. The town was previously known as Ego, which was the name assigned to the post office when it was established in 1895. The post office name was officially changed to Coleman on September 10, 1910.Notable People Born in ColemanJohn H. Ross (WWII pilot) - Awarded Distinguished Flying Cross twice, and is subject of the documentary film John Ross: American.SourcesShirk, George H. Oklahoma Place Names. Norman, Oklahoma: University of Oklahoma Press, 1965.