Complex sentence: Galveston is named for the area which includes Galveston Island and Galveston Bay which was first named Galvezton after Viceroy Bernardo de Gálvez, an ally of the United States during the American Revolution.
Split into simpler sentences: Galveston is named for the area which includes Galveston Island and Galveston Bay. It was first named Galvezton after Viceroy Bernardo de Gálvez, an ally of the United States during the American Revolution.