Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Union City is a village in Darke County, Ohio, United States. The population was 1,767 at the 2000 census. Union City was platted in 1838 and incorporated on December 6, 1853. Incorporation came during a period of growth occasioned by the opening of a line of the Greenville and Miami Railroad through the community on December 12, 1852.