Samuel R. Frost, state representative and district judge, was born to William and Louisa Frost in Montgomery County, Texas, on March 1, 1846; the family moved to Navarro County that same year. Frost's parents had come to Texas from North Carolina in 1845. He grew up on his father's farm in the Dresden-Raleigh community and was educated in Navarro County schools until the outbreak of the Civil War. At the age of seventeen, he entered the Confederate Army as a private in Company I of the Nineteenth Texas Cavalry. He traveled with this unit to Arkansas, Missouri, and Louisiana during the war. He subsequently returned to Texas and began a farming career, which he gave up in 1867 after Texas suffered an unusual blizzard. Frost attended school in Alvarado in 1867–68. He taught in county schools and studied law in the office of Clinton M. Winkler from 1868 to 1870, when he was admitted to the bar in Navarro County.
He was appointed county attorney for Navarro County in 1871 and elected county judge on February 15, 1876. He was unanimously elected to represent his district in the Texas House of Representatives on November 5, 1878. He became district judge of the Thirteenth Judicial District in 1886 and served as flotorial representative of Johnson, Hill, Ellis, and Navarro counties in the Twenty-first Legislature in 1889. Frost later was tendered a position as judge of the Court of Civil Appeals for the state of Texas but declined. He was a strict believer in states' rights and a staunch Democrat. He was one of the organizers of the first water and gas plants of Corsicana. After his service in the Texas government, he returned to Navarro County to practice law and became the attorney for the Cotton Belt and the Houston and Texas Central railroads.
He married Mary L. "Mollie" Winkler, daughter of Clinton Winkler, on June 4, 1872. They had nine children. On January 1, 1908, Frost died during an operation in Fort Worth. He was buried in Corsicana. Frost, in Navarro County, was named for him.