Treaty of Portsmouth (1905)

Russia and Japan had competing interests in Korea and Manchuria, and war broke out in 1904. By 1905, heavy military and financial costs made a settlement attractive to both governments. At Japan’s request, U.S. President Theodore Roosevelt helped bring the parties to negotiations at Portsmouth, New Hampshire. Talks began in August, and the treaty was signed on 5 September 1905 (23 August in the Old Style calendar used in the treaty text).

Russia acknowledged Japan’s predominant political, military and economic interests in Korea. The two governments agreed to evacuate Manchuria and restore occupied areas there to China, while Russia transferred to Japan its lease rights in the Liaodong Peninsula, including Port Arthur and Talien, and the associated railway rights specified in the treaty. Russia also ceded the southern part of Sakhalin Island to Japan. The agreement addressed fishing rights, prisoners of war, and commercial relations. Japan abandoned its demand for a monetary indemnity; Russia was not required to pay Japan’s war costs.

The treaty ended the war and reshaped the balance of power in Northeast Asia. It strengthened Japan’s position in Korea and southern Manchuria, while limiting Russian influence in the region. The treaty did not itself annex Korea; rather, it recorded Russia’s recognition of Japan’s predominant interests there. Public reactions in Japan included protests because the settlement lacked an indemnity, while Russian opposition also objected to the loss of southern Sakhalin. Japan’s growing influence in Korea led to further developments outside the treaty itself.

Roosevelt’s mediation helped bring the negotiations to a conclusion, though the parties themselves negotiated and signed the settlement. In 1906, Roosevelt received the Nobel Peace Prize for his role in ending the conflict between Japan and Russia. The Treaty of Portsmouth is distinct from later agreements concerning Korea and East Asia; its immediate function was to establish peace between the two belligerents and set out their postwar arrangements.