John G. A. Leishman (October 5, 1906 – June 10, 1909) Oscar S. Straus (October 4, 1909 – September 3, 1910) William Woodville Rockhill (August 28, 1911 – November 20, 1913) Henry Morgenthau, Sr. (December 11, 1913 – February 1, 1916) Abram I. Elkus (October 2, 1916 – April 20, 1917)