Born in Elkton, Kentucky, the county seat of Todd County, he was the son of John Oliver and Ellen (née Reeves) McReynolds, both members of the Disciples of Christ church.
John Oliver McReynolds was active in business ventures and served as a surgeon in the Confederate army during the Civil War.
The house in which James Clark McReynolds was born still stands; it was listed on the National Register of Historic Places in 1976.
He graduated from the prestigious Green River Academy and later matriculated at Vanderbilt University, Nashville, Tennessee, graduating with status one year later as a valedictorian in 1882.
At the University of Virginia School of Law, where he studied under John B. Minor, "a man of stern morality and firm conservative convictions," McReynolds completed his studies in fourteen months.
He again graduated at the head of his class.
McReynolds received his law degree in 1884.

He was secretary to Senator Howell Edmunds Jackson, who later became an associate justice, in 1893.
McReynolds practiced law in Nashville and served for three years as an Adjunct professor of Commercial Law, Insurance, and Corporations at Vanderbilt University Law School.

He became active in politics, running unsuccessfully for Congress in 1896 as a "Goldbug" Democrat.
As head of the Tennessee delegation to the 1896 Democratic Convention, he wrote the party's "sound money" plank.
Under Theodore Roosevelt, McReynolds served as Assistant Attorney General from 1903 to 1907, when he resigned to take up private practice with the noted law firm of Guthrie, Cravath, and Henderson (later renamed Cravath, Swaine & Moore) in New York City.
Born in Elkton, Kentucky, the county seat of Todd County, he was the son of John Oliver and Ellen (née Reeves) McReynolds, both members of the Disciples of Christ church. John Oliver McReynolds was active in business ventures and served as a surgeon in the Confederate army during the Civil War. The house in which James Clark McReynolds was born still stands; it was listed on the National Register of Historic Places in 1976. He graduated from the prestigious Green River Academy and later matriculated at Vanderbilt University, Nashville, Tennessee, graduating with status one year later as a valedictorian in 1882. At the University of Virginia School of Law, where he studied under John B. Minor, "a man of stern morality and firm conservative convictions," McReynolds completed his studies in fourteen months. He again graduated at the head of his class. McReynolds received his law degree in 1884.
He was secretary to Senator Howell Edmunds Jackson, who later became an associate justice, in 1893. McReynolds practiced law in Nashville and served for three years as an Adjunct professor of Commercial Law, Insurance, and Corporations at Vanderbilt University Law School.
He became active in politics, running unsuccessfully for Congress in 1896 as a "Goldbug" Democrat. As head of the Tennessee delegation to the 1896 Democratic Convention, he wrote the party's "sound money" plank. Under Theodore Roosevelt, McReynolds served as Assistant Attorney General from 1903 to 1907, when he resigned to take up private practice with the noted law firm of Guthrie, Cravath, and Henderson (later renamed Cravath, Swaine & Moore) in New York City.
James Clark McReynolds