The Russo-Japanese War, was a conflict that grew out of the rival imperialist ambitions of the Russian Empire and the Empire of Japan over Manchuria and Korea. The major theatres of operations were Southern Manchuria, specifically the area around the Liaodong Peninsula and Mukden, and the seas around Korea, Japan, and the Yellow Sea.
The Russians were in constant pursuit of a warm water port on the Pacific Ocean, for their navy as well as for maritime trade. The recently established Pacific seaport of Vladivostok was operational only during the summer season, but Port Arthur would be operational all year. From the end of the First Sino-Japanese War to 1903, negotiations between the Tsar's government and Japan had proved futile. Japan chose war to protect its exclusive dominance in Korea. Russia, meanwhile, saw war as a means of distracting the populace from government repression and rallying patriotism in the aftermath of several general strikes.
The resulting campaigns, in which the fledgling Japanese military consistently attained victory over the Russian forces arrayed against them, were unexpected by world observers. These victories, as time transpired, would dramatically transform the balance of power in East Asia, resulting in a reassessment of Japan's recent entry onto the world stage. The embarrassing string of defeats increased Russian popular dissatisfaction with the inefficient and corrupt Tsarist government and proved a major cause of the Russian Revolution of 1905.
The Russo-Japanese War was a source of pride among many in the Japanese military and civilian branches, as it was seen as the first time a modern war was fought where people of color beat whites. Many in the Japanese High Command hoped that the war with the United States would be concluded just as swiftly as the war with the Russians had been with a decisive battle much like the Battle of Tsushima.
The fact that the Japanese won the Russo-Japanese War was still a sore spot for many Russians. Soviet Premier Vyacheslav Molotov was only a boy during the war, but decades later, in 1964, he still remembered his country's humiliation. Because of this, he regarded the Japanese Empire as a threat in spite of that countries lack of nuclear armaments at the time. He vowed that one day, the Soviet Union would settle the score.