Baron Greenwich is a title that has been created twice in British history. The first creation came in the Peerage of Great Britain in 1767 when Lady Caroline Townshend was made Baroness Greenwich, in the County of Kent, with remainder to the male issue by her second husband, Charles Townshend. She was the daughter of Field Marshal John Campbell, 2nd Duke of Argyll, who had been created Earl of Greenwich in 1715 and Duke of Greenwich in 1719, titles which became extinct on his death in 1743. As Caroline's two sons by her second husband predecesed her, the title became extinct upon her death in 1794. The second creation came in the Peerage of the United Kingdom in 1947 when Lieutenant Philip Mountbatten, the husband of Princess Elizabeth (now Queen Elizabeth II), was made Baron Greenwich, of Greenwich in the County of London. He was made Earl of Merioneth and Duke of Edinburgh at the same time.
Baronesses Greenwich; First creation (1767) 
- Caroline Townshend, 1st Baroness Greenwich (1717–1794)
Barons Greenwich; Second creation (1947) 
- Prince Philip, Duke of Edinburgh (b. 1921)