Complex sentence: From 1638-1655 the Delaware Valley was part of New Sweden, which had been established by Peter Minuit, who had been Director of New Netherland, and was responsible for the famous purchase of the island of Manhattan.
Split into simpler sentences: From 1638-1655 the Delaware Valley was part of New Sweden. It was established by Peter Minuit, former Director of New Netherland who had purchased the island of Manhattan.