Duke Shelby’s mother in Peaky Blinders is Zelda. She was a Romani woman who had a brief relationship with Tommy Shelby before World War I, and she later raised Duke on her own.

What the show implies

  • Duke was born after Tommy left for war, so Tommy did not know he existed for years.
  • Esme is the one who later tells Tommy about Duke and his mother.
  • The series presents Zelda as Duke’s biological mother, not a Shelby family member by marriage.

In context

Zelda’s role matters because it explains why Duke grows up outside the Shelby family and only later enters Tommy’s world. The story frames Duke as Tommy’s hidden firstborn son, with Zelda as the mother who kept him alive and raised him away from Birmingham.

TL;DR: Duke’s mother was Zelda.