Simplify the following text for a Grade 8 native English-speaking person.
Original: By 473 BC , after the death of Phrynichus , one of his chief rivals , Aeschylus was the yearly favorite in the Dionysia , winning first prize in nearly every competition .
Simplified: By 473 BC , Aeschylus was the yearly favorite in the Dionysia , winning first prize in nearly every competition .