Simplify the following text for a Grade 6 native English-speaking person.
Original: He served as the nominal head of government from 1742 until his death in 1743 , but was merely a figurehead for the true leader of the government , Lord Carteret , the Secretary of State for the Northern Department .
Simplified: Wilmington served as the head of government from 1742 until his death in 1743 , but was a leader in name only .