Chattanooga is an unincorporated community located in Mercer County, Ohio. Chattanooga has a population of 418, with approximately 49.51% males and 50.49% females. A post office called Chattanooga was established in 1882, and remained in operation until 1905. Chattanooga is derived from the Cherokee name for "crow's nest". In 1907, Chattano…Chattanooga is an unincorporated community located in Mercer County, Ohio. Chattanooga has a population of 418, with approximately 49.51% males and 50.49% females. A post office called Chattanooga was established in 1882, and remained in operation until 1905. Chattanooga is derived from the Cherokee name for "crow's nest". In 1907, Chattanooga had 100 inhabitants. Cities near Chattanooga, Ohio are Celina, OH and New Haven, IN.