[1] His great-grandfather, William Mitchell, was born in Edgefield County, South Carolina and owned a farm near Flat Rock.

[1] His father was Russel Crawford Mitchell, a wealthy lawyer and lumber industrialist who served in the Texas Brigade, an infantry formation of the Confederate States Army during the American Civil War.

Gospero Sweet and Ann Munnerlyn, who was from Quincy, Florida and met his father while serving as a nurse during the war.

[2] The Mitchells first lived in a two-story, six-room frame cottage at 296 Cain Street in an affluent part of Atlanta inhabited by old families, where all of their children were born.

[3] Mitchell took his family on annual vacations to New York City or Boston, and sometimes they visited Albany by sailing up the Hudson River in a steamship.

[3][11] A year later, as his law practice prospered, he moved the family into a large, twelve-room, brick Victorian mansion at 179 Jackson Street.

In 1909, Mitchell purchased a large lot at 1149 on Peachtree Street, where he built a two-story Colonial Revival mansion with terraces.

[16] Mitchell served as president of the Atlanta Board of Education from 1911 to 1912, during which he abolished corporal punishment in public schools.