Political map of East Asia and the Western Pacific 30 January 1902 (Anglo-Japanese Alliance): During the Boxer Rebellion, Russia had occupied Manchuria (Russian invasion of Manchuria (1900)). Suspicious of Russian intentions in the region and wary of its alliance with France (Franco-Russian Alliance), Britain and Japan signed a defensive agreement (Anglo-Japanese Alliance), promising to come to each other's aid should either of them get involved in a war with two or more powers.