Arthur Henderson
In 1908 he was elected Leader of the Labour Party.  He resigned in 1910.  In 1914 he was elected leader again when Ramsay MacDonald resigned. In 1915,  Prime Minister H. H. Asquith's created a coalition government, Henderson became the first member of the Labour Party to become a member of the Cabinet, as President of the Board of Education. In 1916, David Lloyd George forced Asquith to resign and replaced him as Prime Minister. Henderson became a member of the small War Cabinet with the post of Minister without Portfolio. He resigned on 11 August 1917 after his proposal for an international conference on the war was rejected by the rest of the Cabinet.