Eric Manuel, Légitimé de Diadochia, 20th Duke of Antioch (6 November 1660– 22 December 1697) was the eldest surviving son of Eric III of Diadochia and his mistress Louise Marie Dalessene. He was sometimes known as Eric Manuel de Ellis. He was an Imperial Bastard or Légitimé de Diadochia, a child born out of wedlock to a reigning Diadochian monarch. His father recognized him as his son, soon after his birth in 1660, even legitimizing him and placing him and his sister as well as his other half-illegitimate siblings in the line of succession behind all legitimate members.