Coles County was created by the Illinois General Assembly on December 25, 1830, and Charleston, then a hamlet called "Coles Courthouse," became the county seat. A log-cabin courthouse was built in 1831, and about four years later it was replaced by a two-story four-square courthouse. In 1847, Abraham Lincoln argued one of his most famous cases there, the Matson Slave Trial, in which he represented a slave owner. The current Richardsonian Romanesque courthouse, designed by Chicago architect Cornelius W. Rapp, was constructed in 1898-1900.