US Congressman. He was born one of six children (he also had four half-siblings) to Dr. James Johnson and Jane Leeper in Smithland, Kentucky. He was educated and attended private schools. He moved to Owensboro, Kentucky, in 1836, and then studied law, and was admitted to the bar in 1841. He commenced his practice of law in Owensboro, Kentucky, shortly thereafter. On April 22, 1850, he married Harriotte N. Triplett in Owensboro, Kentucky, and the couple would have two children together. He entered politics and he was elected as a Member of the Kentucky State House of Representatives in 1844. He then decided to run for a seat in the United States Congress and was elected. A Member of the Whig Party, he then served Kentucky's 2nd District (Thirty-First Congress) in the United States House of Representatives from 1849 to 1851. He was nominated for reelection but declined to accept the offer in 1850. After his term in the United States Congress expired on March 3, 1851, he was succeeded in office by United States Representative Benjamin Edwards Grey. He then resumed his practice of law and also engaged in the agricultural business in Owensboro, Kentucky. He lastly was appointed and served as a Judge of the Daviess County, Kentucky, Circuit Court from May 2, 1867, to September 2, 1867. He then again resumed his practice of law and agricultural pursuits until his death. He committed suicide by shooting himself through the heart with a rifle on February 12, 1877, at the age of 58. Apparently he had been suffering from mental depression and ill health. Following his funeral, he was buried in the Rosehill Elmwood Cemetery in Owensboro, Kentucky. His wife Harriotte passed away on July 27, 1882, at the age of 50, and she was buried with her husband. His brother William Sylvester Johnson became a successful doctor, and his other brother Richard Woodhouse Johnson became a Major General who served with the Union Army during the American Civil War. His son Philip Triplett Johnson also became a successful doctor.