Walnut Grove Plantation was built by Charles Moore on land granted to him by King George III. It was farmed by his 10 children and generations of descendants, enslaved people and tenant farmers. During the Revolutionary War, the Moores, including daughter Margaret Catherine Moore-Barry and son Thomas Moore, supported the Patriot cause. Local militia mustered at Walnut Grove prior to the Battle of Cowpens, where Thomas Moore fought with the Spartan Regiment. Tradition says Margaret Catherine was a scout and warned the militia of the coming Loyalists. She was later named the Heroine of the Battle of Cowpens, the turning point in the War for Independence. Loyalist William "Bloody Bill" Cunningham raided the plantation in November 1781 and killed a Patriot soldier sheltered by the Moores. During the American Revolution, the Upcountry of South Carolina played a significant role in the final outcome of the war. One of the local militia, formed in response to the Fall of Charleston in 1780, was the Spartan Regiment. During the formation of a new government after the war was won, Spartanburg County was founded and named after the men who were instrumental in winning freedom.