Pope John XXIII (antipope)

Pope John XXIII was the genuine pope from 1958 to 1963, known for convening the Second Vatican Council. However, some individuals mistakenly believe he was an antipope—a claim unsupported by mainstream Catholic history. An antipope is someone who falsely claims to be the pope, typically in opposition to the legitimately elected pope. In John XXIII's case, he is recognized universally as the authentic pope, and there is no credible evidence to suggest he was an antipope.