The Empire of Japan is the Worlds oldest continuously existing nation tracing its routes back to 660bc. It has existed in its current form since the 1890's and the reign of Emperor Meji who established the supremacy of the Emperor and the Diet over the Shogun. Japan was isolated for nearly six hundred years prior to the 1850's but since the end of its isolationism quickly established itself as being equal to the western powers, Indeed even to this day Japan is the only Permanent member of the League of Nations high council that's ethnic group is not primarily made up of Europeans. It is the closest ally of the Anglo-Dutch Union and has been a member of the North Seas Alliance since its foundation.
Japan's alliance with the Union helped spark the most devastating conflicts of the century, In 1905 during the Russo-Japanese war Russian warships fired on British trawlers. The Union Parliament which had been relucant to act previously now seized the war with both hands and sparked WWI, a conflict that saw Japanese control of Korea ensured by force of Arms and the United States agree to the demands over the control of the Philippines. Japan was also involved in the second world war where it faced a hostile China and Russia across the Korean border. A series of successful attacks saw Japan emerge as the undisputed master of the western pacific, especially now that the Union had committed itself to no further activity's east of Singapore. Conflict with the Isolationist USA threatened to drag the world to the brink of Nuclear destruction but both sides avoided full blown conflict, the issue only being resolved by Japan siding with Beatrix against the USA in the Civil War.