Simplify the following text for a Grade 8 native English-speaking person.
Original: The King 's anger at being forced to marry Anne of Cleves was the opportunity Cromwell 's conservative opponents , most notably the Duke of Norfolk , needed to topple him .
Simplified: The king 's marriage to Anne of Cleves was a disaster for Cromwell . It was the opportunity that Cromwell 's opponents ( most notably the Duke of Norfolk ) needed to press for his downfall .