When Pope Julius died in 1513, the next pope, Leo X, called in three architects, Giuliano da Sangallo, Fra Giocondo and Raphael. Sangallo and Fr Giocondo both died in 1515. Raphael made a big change to the plan. Instead of having a Greek Cross, he decided to change the plan to a Latin Cross, which had a long "nave" and "aisles" like the old basilica.