(born Nov. 15, 1397, Sarzana, Republic of Genoa — died March 24, 1455, Rome) Pope (1447 - 55). Soon after his election, he ended the schism caused by the rivalry between popes and church councils. He restored peace to the Papal States, won Poland's allegiance, and gained the support of Austria by promising to crown Frederick III as Holy Roman emperor. Nicholas initiated the Peace of Lodi (1455) in order to end strife in Italy, and he tried to stamp outsimony and other corrupt practices in the church. A patron of art and scholarship, he rebuilt many of Rome's architectural treasures and founded the Vatican Library. Although Nicholas was the first of the Renaissance popes, his failure to promote real religious reform helped bring about the Reformation of the 16th century.