title: Restoration of the Sistine Chapel frescoes
context: The Sistine Chapel was built by Pope Sixtus IV within the Vatican immediately to the north of St. Peter's Basilica and completed in about 1481. Its walls were decorated by a number of Renaissance painters who were among the most highly regarded artists of late 15th century Italy, including Ghirlandaio, Perugino, and Botticelli.[1] The Chapel was further enhanced under Pope Julius II by the painting of the ceiling by Michelangelo between 1508 and 1512 and by the painting of the Last Judgment, commissioned by Pope Clement VII and completed in 1541, again by Michelangelo.[2] The tapestries on the lowest tier, today best known from the Raphael Cartoons (painted designs) of 1515–16, completed the ensemble.
question: Who led the conservation-restoration of the frescoes of the Sistine Chapel?
answers: Pope Sixtus IV