United States
President Theodore Roosevelt
Theodore Roosevelt Jr. was the 26th President of the United States from 1901 to 1909. He played a major role in ensuring the success of the Portsmouth Peace Treaty. Roosevelt was concerned about power balance in the far east, and was concerned about China's growing role in the region and China's relationship with Russia. He was concerned the war would escalate into a larger conflict that would involve America. Roosevelt used behind-the-scenes negotiations to bring about major compromise. Without his efforts to bring together Russia and Japan despite their initially opposed stances, compromise would not have brought about peace. Roosevelt won the Nobel Peace Prize in 1906, largely as a result of success in negotiating the conditions of peace at the Portsmouth Peace Treaty in 1905.
Herbert Peirce
Herbert Peirce was a diplomat who was the Third Assistant Secretary of State from 1901 to 1906. He was named by President Roosevelt to arrange the negotiations of the Treaty. While the Russians and Japanese wanted Roosevelt to preside personally, he instead sent Herbert Peirce to represent him. Peirce played a critical role as a neutral third party in the negotiations. He made sure protocols were followed and that both Russian and Japanese interests were represented in the negotiations. Peirce's efforts led to compromise on both sides.
Japan
Emperor Meiji
The emperor of Japan from 1868 to 1912, he left the matters of state to statesmen and military leaders. Emperor Meiji remained at the palace and followed both the war and the treaty from Japan. He was for compromises and was very helpful with the treaty.
Foreign Minister Jutaro Komura
Jutaro Komura was the Foreign Minister of Japan at the time. Japanese Prime Minister Katsura selected him to represent Japan at the conference. Komura worked with Sergei Witte, the Russian representative, and Herbert Peirce of the United States to find compromise to end the war without much feuding. He was instrumental in making the final proposal that achieved peace.
Russia
Czar Nicholas II
Czar Nicholas II of Russia was the last Emperor of Russia, and ruled at the time of the treaty. He was held responsible for Russian involvement in the war. He did not attend the delegation in Portsmouth, but followed the negotiations closely. Despite the fact that Russia was losing the war, Nicholas wanted to maintain Russia's dignity as a great power. He was willing to risk more losses to avoid compromise. He was difficult to work with, but in the end helped resolve the conflict peacefully.
Count Sergei Witte
Sergei Witte was selected by Czar Nicholas II to negotiate on Russia's behalf. He was a tough negotiator and refused to compromise on many of Russia's positions. Ultimately, Russia lost the war, but he negotiated a strong final position for Russia. Witte held out on key Russian positions, including refusing to give up on Russian control of the island of Sakhalin, which both Russia and Japan wanted to hold. He also refused to compromise on Japan's demand for indemnity and for Russia to pay all costs of the war. He worked with Komura to compromise on most of Japan's proposals and negotiated a final agreement on both indemnity and Sakhalin Island.