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Mercer County

Mercer County is named for Hugh Mercer, who was a physician and general during the American Revolutionary War and who died at the Battle of Princeton.


Surrounding County Courthouses: 

N – Rock Island County

E – Henry County and Knox County

S – Warren County and Henderson County

W – Louisa County, Iowa


Created:  January 13, 1825                                                        Map of Illinois highlighting Mercer County

County Seat:

Boston        1835 – 1837

Millersburg  1837 – 1857

Aledo           1857 – present


County Courthouse – Aledo


Location:  100 SE 3rd Street / South College Avenue

Built:  1894 – 1895

Style:  Romanesque

Architect:  Mifflin Emien Bell

Contractor:  L L Leach & Sons


Description:  The building faces north and is a three story course Beria sandstone structure. The building is located on spacious landscaped grounds in the center of Aledo. The north front of the square shaped building has two small towers with turrets rising on either side of the first story portico. The east and west wings extend from the main building. On the center of the roof is a large square clock tower with turrets and peaked roof. 


See:  The architect, Mifflin Emien Bell also designed the courthouse in DuPage Countyand courthouses in Iowa in Marion County and in Wisconsin in Monroe County. 


See:  The 14th Judicial District includes Henry CountyRock Island County and Whiteside County.


History:  The county was created in 1825 and was attached to Schuyler County until 1826, then to Peoria County until 1831, and finally to Warren County until organized in 1835 when Boston was selected as the county seat. In 1837, the county seat was moved to Millersburg and then to Keithsburg in 1847. In 1856, the county seat was moved to Aledo and the first courthouse was built. The second and present courthouse was constructed in 1894 to 1895 at a cost of $60,000.



County Courthouse – Aledo









Photos taken 2008