Complex sentence: Due to political reversals in England, Carteret was unable to attend to his colonial interests until 1742, when he appointed the first of several agents to operate on his authority for the district that he never visited in person.
Split into simpler sentences: Due to political reversals in England, Carteret was unable to attend to his colonial interests until 1742. Then he appointed the first of several agents to operate on his authority for the district that he never visited in person.