Battle of Belmont, Missouri - Grant Vs. Polk. November 7, 1861. The Battle of Belmont was fought on November 7, 1861 in Mississippi County, Missouri. It was the first combat test in the American Civil War for Brig. Gen. Ulysses S. Grant, the future Union Army general in chief and eventual U.S. president, who was fighting Major General Leonidas Polk. Grant's troops in this battle were the "nucleus" of the Union Army of the Tennessee.