Old Fort Massac was the site where the French under Charles Phillippe Aubry completed a fort called Fort Ascension, later known as Fort Massac, on June 20, 1757. The French destroyed it in 1764 before the territory passed to the British. On the same spot, the United States completed a second fort on March 31, 1794, and a garrison occupied it until its final abandonment in 1814. George Rogers Clark, on his way to Kaskaskia, entered the Illinois Country with his regiment at the mouth of Fort Massac Creek, one mile above the fort site, on June 28, 1778, and it was probably here that a flag representing the sovereignty of the United States was first unfolded in Illinois. At an unknown place between this site and the mouth of the Ohio River, Charles Juchereau de St. Denis built a trading post and tannery in the autumn of 1702, and Father Jean Mermet came to this first European settlement in the Ohio Valley to preach to the Indians.