As northern Illinois opened to settlement in the 1830s, however, public pressure grew for the capital to be relocated to a location closer to the geographic center of the state.

[4] A caucus of nine Illinois lawmakers, including the young Whig Party lawyer Abraham Lincoln, led the effort to have the capital moved to the Sangamon County village of Springfield.

Their efforts were successful in 1837, when the Illinois General Assembly passed a law creating a two-year transition period with the goal of moving the capital to Springfield in 1839.

It was to the same chamber, in May 1865, that his body was returned to lie in state, arriving from Washington, D.C., prior to final burial in Springfield's Oak Ridge Cemetery.

[6] As a result of economic growth spurred by the American Civil War and consequent industrialization, this fifth or Old State Capitol was, by the 1870s, too small to serve the purpose for which it had been built.

Senator Barack Obama officially announced his candidacy for President of the United States at this location, and in August 2008 he formally introduced his vice-presidential candidate, Joe Biden, with the building as a backdrop.

It used the Old State Capitol, which incorporated a courtroom for the Illinois Supreme Court where Lincoln pleaded key cases in his legal career, as a backdrop.