On August 7, 1914, the Japanese government received an official request from the British government for assistance in destroying the German raiders of the Kaiserliche Marine in and around Chinese waters. Japan sent Germany an ultimatum on August 14, 1914, which went unanswered; Japan then formally declared war on the German Empire on August 23, 1914.
Japanese forces quickly occupied German-leased territories in the Far East. On September 2, 1914, Japanese forces landed on China's Shandong Province and surrounded the German settlement at Tsingtao (Kiautschou).
During October, acting virtually independently of the civil government, the Japanese navy seized several of Germany's island colonies in the Pacific - the Mariana, Caroline, and Marshall Islands - without resistance.
The Japanese navy conducted the world's first naval-launched air raids against German-held land targets in Shandong province and ships in Qiaozhou Bay from the seaplane-carrier Wakamiya.
The Siege of Tsingtao concluded with the surrender of German colonial forces on November 7, 1914.