Northampton County Courthouse Northampton County was founded on March 6, 1752. The first court proceedings were held in taverns. The first court house was built in 1765 in Centre Square, then known as "the Great Square." The current courthouse, located on Seventh and Walnut Streets, was designed by Architect G. Graham, Esquire and was built in 1861. Easton, PA 5/10/2013