Simplify the following text for a Grade 6 native English-speaking person.
Original: His reign marked a high point for France during the Hundred Years ' War , with his armies recovering much of the territory ceded to England at the Treaty of BrÃ tigny .
Simplified: His reign marked a high point for France during the Hundred Years ' War . His armies recovered large parts of the territory that had been given to England at the Treaty of BrÃ tigny .