Complex sentence: He strove to maintain good relations between the two countries, although he was unable to prevent the War of Jenkins'Ear breaking out in 1739 he later successfully kept Spain neutral when the Seven Years' War broke out in 1756.
Split into simpler sentences: He strove to maintain good relations between the two countries, but was unable to prevent the War of Jenkins'Ear breaking out in 1739. He later successfully kept Spain neutral when the Seven Years' War broke out in 1756.