George I became king of England in 1714 when Queen Anne died without an heir. As he spoke only German, he relied on elected members of parliament (MPs) from the Whig party to govern. George II's reign saw Sir Horace Walpole become the first prime minister and remain in power for over 20 years. George III's reign was marked by military conflicts including the American War of Independence and the French Revolution. He later suffered from mental illness. During the Augustan age, political and intellectual leaders saw England as the heir to Rome and its stable government and growing empire. Coffee houses flourished as intellectual centers for debate.