Washington County is located in the southwestern corner of Illinois. It is bordered by the Mississippi River to the west and the Illinois River to the east. The county seat is Nashville.

The county has a total area of 545 square miles, of which 543 square miles is land and 2 square miles is water.

Washington County is governed by a seven-member Board of Commissioners. The board is elected from seven districts within the county. The board is responsible for setting the county budget, levying taxes, and making policy decisions.

The county is also served by a state's attorney, sheriff, coroner, and treasurer.

For the most up-to-date and in-depth information, please check the public records links below.