1864–1928, U.S. Secretary of State (1915–20), b. Watertown, N.Y. An authority in the field of international law, he founded the American Journal of International Law in 1907 and remained an editor of it until his death. He served as counsel for the United States in several international disputes, and he became attached (1914) to the Dept. of State. President Wilson appointed him to succeed William Jennings Bryan as Secretary of State after the latter's resignation. Lansing was a strong, although not outspoken, advocate of U.S. participation in World War I on the side of the Allies. Because Wilson largely conducted foreign policy himself with his political confidant Edward M. House, Lansing had little influence in the negotiations that led to the declaration of war against Germany. In 1917, Lansing concluded with Kikujiro Ishii of Japan the Lansing-Ishii agreement, which gave U.S. recognition to Japan's special interests in China, while reaffirming the Open Door policy. Lansing, who was nominal head of the U.S. commission to the Paris Peace Conference, lost Wilson's confidence because he did not regard the Covenant of the League of Nations as essential to the peace treaty. The breach between the two was completed when Wilson learned that during Wilson's illness Lansing had on several occasions called the cabinet together for consultations. In Feb., 1920, at Wilson's request, Lansing resigned. He later returned to his law practice. His writings include The Big Four and Others at the Peace Conference (1921), The Peace Negotiations (1921), and Notes on Sovereignty (1921). The War Memoirs of Robert Lansing (1935) was published posthumously.
- See studies by D. M. Smith (1958, repr. 1972) and B. F. Beers (1962).