St. Francois County remained firmly in Union hands throughout the war. The county was important to the Union because of its lead production. The St. Louis Iron Mountain Railroad also ran through the county, permitting rapid deployment of troops from St. Louis if necessary. Despite the heavy concentration of Union troops, there was Confederate guerrilla activity in St. Francois County throughout the war.

  Sam Hildebrand was one of the most notorious southern guerrilla leaders to operate in the Southeast Missouri Region. He was born in 1836 in a home that had been built by his father near the Big River in 1832. Hildebrand's reign of terror began following the murder of his brother by Union vigilantes in Ste. Genevieve County at the start of the war. Hildebrand himself was attacked by Union soldiers at his farm in the Flatwoods area of St. Francois County. The wounded Hildebrand was taken to a rebel camp in Greene County, Arkansas where he was commissioned a major by Confederate General Jeff Thompson.

  When he recovered, Hildebrand returned to the county and killed the two men he believed to be responsible. In retaliation, Federal troops burned the Hildebrand home and killed his 13 year old brother. Neighbors built a log cabin near the burned-out family home for his mother. Operating from a Confederate base in Arkansas, Hildebrand's knowledge of the area allowed him to make repeated forays into Southeast Missouri, often returning to the small community of Big River Mills north of Bonne Terre for supplies. A network of Confederate sympathizers provided Hildebrand and his men shelter and food, allowing them to escape Union traps.

  For several weeks in 1864, Hildebrand and his men commandeered the St. Joe Lead Mines and manufactured lead for General Sterling Price to be used during his invasion of Missouri. Afterwards Price ordered the furnaces blown up so that they would not fall into Federal hands. The lead was stored near Big River Mills. While recovering the lead, Hildebrand's men were attached by federal troops under Major Samuel Montgomery at Tyler's Mill at Big River. According to Montgomery, twenty one confederates were killed.

  Hildebrand's raids earned him a hatred which lasted long after the war ended. Sam Hildebrand was killed in Pinckneyville, Illinois by a sheriff's deputy in May of 1872. He was buried in what is now the Hampton Cemetery in Park Hills. The grave is marked by a simple stone. Hildebrand's brother, William, served in the Union army.

  In Park Hills, along old State Route 8, visitors can still view the 164 year old home of Dick Berryman, now a private residence. One of Hildebrand's closest friends, Berryman accompanied Hildebrand on several of his deadly raids into Southeast Missouri. During the war the house served as an underground recruiting center for the Confederate cause. One of Hildebrand's many local hideouts, the cave in St. Francois State Path in northern St. Francois County, still bears his name.