Mercer

Formed April 1, 1820 (63^rd county)

Mercer County (42,528), Celina (10,935)

The masonry Neo-Classical courthouse was constructed in 1923.  It is located at Main, Livingston, Walnut, and Market streets.  United States Highway 127 is Main Street in the town.  Peter M. Hulsken is the building architect.  There was also an 1868 facility.  The building features columns.  Saint Mary was the first county seat until 1839 when Celina became the seat.  Mercer County was established on April 1, 1820 from Darke County as the 63^rd county.  It is named for American Revolutionary War hero Hugh Mercer.  The county seat is named for Salina, New York (obviously the spelling was changed.) 

Mercer County government consists of a sheriff and 3 Commissioners.  Two Common Pleas Court Judges serve Mercer County.  The county is on the western border with Indiana.  Toledo, Ohio is northeast and Dayton, Ohio is southeast of the county.  The county center is 2.6 miles West-Southwest of Celina.  The county is surrounded clockwise by Van Wert, Auglaize, Shelby, and Darke counties and Indiana. 

The area of the county is 463.3 square miles.  It is 36 out of 88 in the state.  It ranks 58 out of 88 in population in the state.  It has a density of 91.8 persons per square mile making it 60 out of 88 in the state.  Mercer County has 52.2% of its population in its incorporated areas.  United States Highway 33 enters the county from the east, Auglaize County, and exits to the northwest, Van Wert County.  The county is a rectangle.  Celina is located slightly east of center in the county.  Celina is the county seat and the largest city.  It is 25.7% of the county population.  The county seat is pronounced SE-LIE-NA.  This county is in the Celina Micropolitan Statistical Area.