A titular see of Thrace, not mentioned by any ancient historian or geographer. However, its bishop, Symeon, attended the Council of Constantinople (Lequien, Oriens Christ., I, 1167). The "Notitiæ episcopatuum" of the tenth to the twelfth and thirteenth centuries mention Leuce among the suffragans of Philippopolis. It is probably the modern village of Copolovo, south of Philippopolis, or Plovdiv, Bulgaria.