On 17 June 1925, he was appointed as Assistant Secretary of State by President Calvin Coolidge. He was subsequently appointed as Under Secretary of State, on May 19, 1927. Olds resigned as Under Secretary of State on 30 June 1928.
He served as the Commissioner of the American Red Cross in Europe, from 1919 to 1921 during the war and as a United States member of the League of Nations tribunals and commissions. In 1929 he became a member of the reparations commission under the treaty of Versailles. He was appointed as a member of the permanent court of arbitration at the Hague in 1931.
He died suddenly on November 25, 1932 in Paris, where he was a member of the council of the International Chamber of Commerce, due to a cerebral hemorrhage.