Born in Cullman, a small city in Alabama, Tatum has one sister. He has French, Irish, and Native American ancestry. His family moved to Mississippi when he was six, although he visits Alabama, where his mother's family still lives. Tatum grew up in the bayous near the Mississippi River, where he enjoyed a rural existence, including "All the rattlesnakes and alligators a boy could possibly chase, fishing every day, Pop Warner football league, stuff like that. "

Tatum was athletic while growing up, playing American football, soccer, track, baseball, and performing martial arts, although he says that "girls were always [his] biggest distraction in school." Tatum initially attended Gaither High School in Tampa, Florida. After his sophomore year, he "had an option either [to attend] a military school or a private school". He chose the private school, Tampa Catholic High School in Tampa, Florida. He graduated in 1998 and was voted most athletic. Afterward, Tatum was awarded a footb