Simplify the following text for a Grade 18 native English-speaking person.
Original: After the second Anglo-Dutch War of 1665 â `` 1667 , England and the United Provinces of the Netherlands agreed in the Treaty of Breda to the status quo : The English kept the island of Manhattan , which the Duke of York ( the future James II , brother of Charles II ) , had occupied in 1664 , renaming the city on that island from New Amsterdam to New York ; while in return Run was formally abandoned to the Dutch .
Simplified: After the second Anglo-Dutch War of 1665 -- 1667 England and the United Provinces of the Netherlands agreed in the Treaty of Breda to the status quo : The English kept the island of Manhattan which the Duke of York ( the future Charles II ) , had occupied illegally in 1664 and renamed from New Amsterdam to New York and Run was officially given to the Dutch .