Washington County

Washington County is located in the southeastern part of the U.S. state of Missouri. As of the 2010 census, the population was 25,195. The county seat and largest city is Potosi. The county was officially organized on August 21, 1813, and was named in honor of George Washington, the first President of the United States.
The French explorers Renault and La Motte entered the area of present-day Potosi in 1722–23. However, no permanent settlements were made until 1763, when François Breton settled near Potosi and began to operate a mine bearing his name. The Bellview Valley, near Caledonia and Belgrade, was settled in 1802 by the families of William and Helen Watson Reed, their sons, Robert, Joseph, and Thomas Reed, William Reed's brother and nephew, Joseph and William Reed, Annanias McCoy, and Benjamin Crow. Washington County was officially organized on August 21, 1813, out of Ste. Genevieve County.

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