His mother, although she would eventually graduate from Temple University, was single and only 16 years old when he was born.

In 1996, Culliver's stepfather and a cousin were shot to death, and his mother was wounded, in a Philadelphia bar fight.

In his senior year, he was credited with 147 tackles and four interceptions, and, although he started only a handful of games on offense, he logged 1,500 all-purpose yards and returned four kickoffs and two punts for touchdowns.

He was the MVP for the East squad in the Offense-Defense All-Star Game after catching three passes for 97 yards, including a 77-yard touchdown reception.

He was considered by Rivals.com as the top player in the state of North Carolina and the third-best wide receiver in the country.

He was also rated the 37th-best defensive back in the nation and the seventh-best player in the state of North Carolina by SuperPrep.

With 12 starts, Culliver made 60 tackles, including 4.5 for losses, as well as three interceptions, three passes deflected, and two forced fumbles.

[11][12] As a rookie, Culliver played all 16 games of the regular season and finished with a total of 35 combined tackles, 7 pass defensed, and 1 interception for 23 yards.

[14] In the 2012 season, Culliver was the 49ers' primary nickelback, and he had a key interception against the Atlanta Falcons in the NFC Championship Game.

[15] San Francisco advanced to Super Bowl XLVII, but lost 34–31 to the Baltimore Ravens.

[16][17] Prior to the Super Bowl during Media Day, Culliver had some strong words for gay players in the NFL.

[26] On September 14, he was suspended for one game for violating the personal conduct policy following misdemeanors that occurred in March 2014.

[31] After starting the season on the physically unable to perform list, Culliver was added to the active roster on November 7, 2016.