Simplify the following text for a Grade 9 native English-speaking person.
Original: Pietro Perugino ( 1446 â `` 1524 ) , born Pietro Vannucci , was the leading painter of the Umbrian school , who developed some of the qualities that found classic expression in the High Renaissance .
Simplified: Pietro Perugino ( 1446 â `` 1524 ) was a leading Italian painter of the Umbrian school . He developed some of the qualities that found classic expression in the High Renaissance .