Cyrus F. Harkey was born around 1844 in Georgia to Miles and Margaret Harkey. His father was a farmer who owned $3,000 of real estate by 1850. The family lived in Cobb County, Georgia, until the 1850s, when they moved to Upshur County, Texas.
He enlisted in the Confederate army on January 2, 1862, and he mustered in as a private in Company E of the 14th Texas Cavalry. The regiment took part in the Battle of Stones River, the Battle of Chickamauga, and the Atlanta campaign. He fell ill in the spring of 1863, and he spent the next several months recovering. He remained in the army until at least March 1864.
Harkey settled in Denton County, Texas, after the war, and he married a woman named Mary around 1870. They had at least two children. He earned a living as a farmer, and by 1910, they were living in Snyder, Texas. He died there of Bright’s disease on April 22, 1912.