Comertown is an unincorporated community in northeastern Sheridan County, Montana, United States. It was founded in 1913. Comertown is at an altitude of 2,270 feet. Although the land around Comertown attracted numerous homesteaders during the first years following the railroad's completion, the region proved to be unsuited for intensive agricultura…Comertown is an unincorporated community in northeastern Sheridan County, Montana, United States. It was founded in 1913. Comertown is at an altitude of 2,270 feet. Although the land around Comertown attracted numerous homesteaders during the first years following the railroad's completion, the region proved to be unsuited for intensive agricultural use, and by the 1920s Comertown was in decline.