Simplify the following text for a Grade 9 native English-speaking person.
Original: On May 13 , 1497 , Savonarola was excommunicated by Pope Alexander VI , and in 1498 , Alexander demanded his arrest and execution .
Simplified: On May 13 , 1497 , Savonarola was excommunicated by Pope Alexander VI . In 1498 , Alexander demanded his arrest and execution .