Who was Luca Signorelli?

Signorelli, The Circumcision
Luca Signorelli (1441-1523) was an Italian painter, born in Cortona. At Loretto he painted a number of frescoes commissioned by Pope Sixtus IV, in the Sistine Chapel the fresco called the "Life of Moses", and for Lorenzo de Medici the picture known as the "School of Pan". But his greatest achievement was a number of frescoes depicting such subjects as the "Fall of Antichrist", "Punishment of the Wicked", and the "Last Days of Earth", in the cathedral in Orvieto.