Roosevelt negotiated Treaty of Portsmouth Nga-Nhật President Roosevelt negotiated Treaty of Portsmouth President Roosevelt negotiated Russo-Japanese War of 1904–05. war between Russia and Japan in 1904 disastrous Russo-Japanese war in 1905 disastrous Russo-Japanese war in 1905 Russo-Japanese War of 1904–05. The Treaty of Portsmouth Russo-Japanese War History.state.gov negotiate negotiated peace between the Japanese and Russians Treaty of Portsmouth disastrous Russo-Japanese war in 1905 negotiated peace between the Japanese and Russians Russo-Japanese War of 1904–05. History.state.gov History.state.gov Vertrag von Portsmouth Russo Japanese War of 1904 bequeathe Treaty of Portsmouth