Dylann Storm Roof was born on April 3, 1994, in Columbia, South Carolina. His parents, Franklin Bennett Roof and Amelia "Amy" Cowles, divorced when he was young but were briefly reconciled at the time of his birth. When Dylann was five years old, his father married Paige Mann, but they later divorced. Reports indicate that Dylann's father was allegedly abusive towards Mann.

Dylann spent most of his childhood in South Carolina but lived in the Florida Keys for around three years, from 2005 to 2008. There is little information about his schooling during that time. Dylann reportedly showed signs of obsessive-compulsive behavior as a child, including a fixation on germs and specific hairstyles. In middle school, he began smoking marijuana and was caught using money to buy it.

Over the years, Dylann changed schools frequently. He attended at least seven schools across two South Carolina counties. At one point, he repeated the ninth grade and later finished it at a different school. By 2010, he stopped attending classes altogether and is believed to have dropped out of school. His family stated that he spent much of his time playing video games and using drugs, having little interest in education.

Before the events that would later define his life, Dylann was living between his father’s and mother’s homes. He was mostly raised by his stepmother. In the months leading up to the attack, he often stayed with a friend from middle school and that friend’s family, where he continued to engage in substance abuse. His uncle expressed worry over Dylann's social withdrawal and lack of direction, noting that Dylann did not have a job or a driver's license and spent most of his time alone.

On the evening of June 17, 2015, Dylann Roof entered Emanuel African Methodist Episcopal Church in Charleston, South Carolina, during a Bible study session. He opened fire with a handgun, killing nine people and injuring one person. Roof was unemployed at the time and living in a neighborhood with a large African American population.

Before the shooting, Roof had expressed extreme racist beliefs and mentioned his intention to start a race war. He had been influenced by events surrounding the deaths of Trayvon Martin and Freddie Gray, discussing them with friends and expressing views against African Americans. Just before the attack, he was recognized as a potential shooter by individuals who had heard his alarming statements.

After the shooting, Roof fled the scene, and law enforcement began a manhunt for him. He was captured the next day, June 18, 2015, during a traffic stop in Shelby, North Carolina. A .45-caliber pistol was found in his car. During questioning by the FBI, Roof confessed to the attack. He stated he was hoping to incite racial conflict.

In the aftermath, Roof faced both state and federal charges, including multiple counts of murder and hate crimes. He was found guilty on all counts in December 2016 and was sentenced to death in January 2017. In South Carolina, he later pleaded guilty to avoid a second death penalty trial, receiving nine consecutive life sentences without the possibility of parole. Roof is currently awaiting execution on federal death row.