antipope [Lat., = against the pope], person elected pope whose election was declared uncanonical and in opposition to a canonically chosen pontiff. Important antipopes were Novatian; Clement III (see Guibert of Ravenna); Nicholas V (see Rainalducci, Pietro); Clement VII (see Robert of Geneva); Benedict XIII (see Luna, Pedro de); John XXIII (or by a different count, John XXII; see Cossa, Baldassare); and Felix V (see Amadeus VIII), who was the last antipope.
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