In August of 1779, the peace and tranquility of this forested hill was broken by the boom of cannons, the crack of musket fire, and the yells of Iroquois warriors. The Continental Army was engaged in battle with the British regulars, Loyalist rangers and 1000 Iroquois Indian warriors. The battle of Newtown was the decisive clash in one of the largest offensive campaigns of the American Revolution. This expedition, known as the Sullivan-Clinton Campaign, had been regarded as punishment to several tribes among the Six Nations of the Iroquois Confederacy who had sided with the British in the war and had attacked frontier settlements.

A stone monument was dedicated at the top of the hill on August 29, 1879, the centennial of the Battle of Newtown. The present granite monument was erected in 1912. During the 1930s, Civilian Conservation Corps crews built and developed many of the present facilities of the park, including a beautiful, rustic lodge. In 1973, Newtown Battlefield Reservation was designated as a historic landmark and placed on the National Register of Historic Places.