The Anglo-Japanese Alliance was a military agreement formed in 1902 between the United Kingdom and Japan. This alliance aimed to counterbalance the influence of Russia in East Asia and ensure mutual support in case of conflict. It marked a significant shift in international relations, as it was the first time a Western power recognized Japan as an equal. The alliance was renewed and expanded in 1911, further solidifying cooperation between the two nations. It played a crucial role during World War I, as Japan joined the Allies against Germany. The alliance ultimately ended in 1923, reflecting changing geopolitical dynamics.