There are 2 US Post Offices in Allen County serving a total of 18,865 residents equating to 9,433 residents per post office. It's estimated that approximately 30,111 packages are handled across the 2 county post offices annually. Allen County is a county located in the U.S. state of Kentucky. As of the 2010 census, the population was 19,956. Its county seat is Scottsville. The county is named for Colonel John Allen, a state senator and soldier who was killed leading the 1st Regiment of Kentucky Rifleman at the Battle of Frenchtown, Michigan during the War of 1812. Allen County is a prohibition or completely dry county. It was formed in 1815 from parts of Barren and Warren counties. Allen County is included in the Bowling Green, KY Metropolitan Statistical Area."