Pope Sixtus V was a vigorous reformer who worked to streamline the administration of the Church and improve its finances. He also oversaw the construction of significant architectural projects in Rome, including the completion of St. Peter's Basilica. Birth name: Felice Piergentile Nationality: Papal States Born: December 23, 1521 Died: August 27, 1590 Pontificate: April 24, 1585 – August 27, 1590