Simplify the following text for a Grade 8 native English-speaking person.
Original: Pope Julius II ( December 5 , 1443 - February 21 , 1513 ) , originally Giuliano Della Rovere , was pope from 1503 to 1513 .
Simplified: Julius II ( c. 5 December 1443 -- 21 February 1513 ) , nicknamed `` The Fearsome Pope '' ( Il Papa Terribile ) and `` The Warrior Pope '' ( Il Papa Guerriero ) , born Giuliano della Rovere , was Pope from 1503 to 1513 .