William Plummer Benton (December 25, 1828 – March 14, 1867) was an American lawyer and soldier who served in both the Mexican–American War and the American Civil War, where he would rise to the rank of brigadier general and, in 1866, after his service had ended, would be awarded the brevet grade of major general.

When Benton was 18 years old, he enlisted as a private in the Mexican War, and fought with gallantry in the mounted infantry at Contreras, Churubusco, Chapultepec and Mexico City.

B. Julian which continued until 1856, when he was elected judge of the Common pleas court, serving one term, until defeated for renomination in 1858.

He led the 8th Indiana in some the earliest fighting of the war during McClellan's Western Virginia campaign of 1861, including the Battle of Rich Mountain.

Also while in Missouri, future Buffalo Soldier Cathay Williams was impressed into serving Plummer's regiment, the 8th Indiana, as cook and laundress.

He served with distinction at the Battles of Port Gibson, Jackson (where he was wounded), Champion Hill, Big Black River, and at the Siege of Vicksburg.