Bartemius "Barty" Crouch, Junior, was captured with the Lestranges, who tortured Frank and Alice Longbottom, parents of Neville Longbottom into insanity.
Bartemius "Barty" Crouch, Junior, is a Death Eater. His backstory is that he was captured with the Lestranges, who tortured Frank and Alice Longbottom, parents of Neville Longbottom into insanity.