Bernard Hopkins Jr. is an American former professional boxer who competed from 1988 to 2016. He is one of the most successful boxers of the past three decades, having held multiple world championships in two weight classes, including the undisputed middleweight title from 2001 to 2005, and the lineal light heavyweight title from 2011 to 2012.

In boxing, the undisputed champion of a weight class is the boxer who simultaneously holds world titles from all recognized major organisations by each other and the International Boxing Hall of Fame. There are currently four major sanctioning bodies: WBA, WBC, IBF and WBO. There were many undisputed champions before the number of major sanctioning bodies recognizing each other increased to four in 2007, but there have only been 19 boxers to hold all four titles simultaneously.