The primary purpose of the Treaty of PortsmouthTheodore Roosevelt, the treaty marked Japan's emergence as a significant global power and established a new balance of power in East Asia. It resulted in territorial gains for Japan in Korea and parts of Manchuria while confirming Russia's weakened influence. The treaty also highlighted America's growing role in international diplomacy, as it was one of the first times a Western nation acted as a mediator in negotiations between two other countries, emphasizing the evolving context of global relations.