Lecturing on the historical significance of the Portsmouth Treaty, a U.S. historian said pluralistic diplomacy, comprising the cooperation of local residents together with mediatory efforts of U.S. President Theodore Roosevelt induced Japan and Russia to reach a compromise and sign the treaty that ended the 1904-5 Russo-Japanese War.

Peter Randall, 64, of Portsmouth, N.H., spoke on the treaty at the lecture held in Tokyo on Tuesday to commemorate the 100th anniversary of the treaty.

The lecture was cosponsored by The Yomiuri Shimbun and the Japan Foundation Center for Global Partnership.

During the lecture, Randall explained, using slides, how the delegations of both Japan and Russia were welcomed by local people when they arrived in Portsmouth.

He pointed out that when the negotiations reached an impasse, local people invited representatives of both countries to attend church services and take part in recreational activities, thus helping the delegates build a good relationship.

He also gave high credits to the persistent mediatory efforts of Roosevelt, who tried to persuade Russian Czar Nicholas II to sign the treaty through the Russian ambassador to the United States.