The three crossword solutions for the term 'Name of 13 Popes' are LEO (3 letters), INNOCENT (8 letters), and Pius (4 letters). LEO was the name of Pope LEO I, who was a bishop of Rome from 440 to 461. INNOCENT was the name of Pope INNOCENT III, who was pope from 1198 to 1216 and is considered one of the most influential popes in history. Pius was the name of Pope Pius XII, who was pope from 1939 to 1958 and was known for his opposition to Nazi Germany during World War II.