David Lloyd George was a British statesman and the only Welsh Prime Minister of the United Kingdom; he is also the only one to have spoken English as a second language, Welsh having been his first. During a long tenure of office, mainly as Chancellor of the Exchequer, he was a key figure in the introduction of many reforms which laid the foundations of the modern welfare state. He was Prime Minister throughout the latter half of World War I and the first four years of the subsequent peace. Although he was the last Liberal to hold that office, his coalition premiership was not supported by most Liberals and the split was a key factor in the decline of the Liberal Party as a serious political force. When he eventually became leader of the Liberal Party a decade later he was unable to lead it back to power.