In 1276 the Portuguese Pedro Julian was elected pope and took the name John. Previous John wore the 19th number. The new pope was to be 20th. But he believed that the list of his predecessors crept into error, and in the history of the papacy was once John. He missed one digit, and announced himself as John XXI. It later emerged that he was mistaken, and no error was, but the numbering could not be reversed. So it happened that John XX never existed. To date, the list ends with John's No. XXIII.