William Thomas Leeper was born in Kentucky and moved to Wayne County in 1857. He purchased in what is present day Mill Spring and Leeper. When the Civil War was on the verge of breaking out, Leeper was strongly opposed to Missouri joining the Confederates in battle. He founded Company D of the Twelfth Regiment of Missouri Militia. The unit, with Leeper in command, hunted for Southern sympathizers. His hunt included mass killings of unarmed men. He allegedly burned villages, cities, and homes. One such story involved the killing of 29 men, referred to as the McGee Massacre or Mingo Swamp Massacre. Leeper and his men sneaked to a house that these Southern sympathizers were staying that night. The McGee clan had just abandoned the Confederate Army to return home to protect their families from Leeper. While the Confederates inside the house sat unarmed, Leeper and his men opened fire. All 29 men died, including Daniel McGee. It is said that he was shot so many times that his torso was almost severed in half.