The first Frenchmen settled in present-day Randolph County c. 1685, and for the colony's first several decades, there was no formal local government: the missionary priests at Kaskaskia settled disputes and dispensed justice among both white men and Indians in the nascent French colony.
[1]: 114 Disaster struck Kaskaskia in the form of the Great Flood of 1844; the highest waters in living memory forced the residents to flee to nearby bluffs, and the town itself was virtually destroyed.
Even the avulsion of 1881, in which the Mississippi River cut off the bend in which Kaskaskia lies and left it attached to Missouri, was much less significant.
[1]: 120 Officials occupied the community's schoolhouse pending the construction of a new courthouse; built and equipped at private expense,[1]: 121 the new building opened in 1850.
A modernist structure with large areas of exterior concrete, its main entrance is situated in a recess at the center of the facade, atop a flight of steps.