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CALIXTUS III

Calixtus III was a pope. He was chosen in 1168 in Rome, as anti-pope to Paschal III, and confirmed by the Emperor Frederick I, in 1178, was obliged to submit to Pope Alexander III. As he was not counted among the legal popes, a subsequent pope, Alfonso Borgia, made pope in 1455, was also called Calixtus III He died in 1458.
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