It is known that Japan and Germany signed agreements on military technological collaboration, both before the 1939 outbreak of World War II, and during the conflict. However, the first air technology interchange occurred during World War I when Japan joined against Germany on the side of the Allies, and Germany lost a Rumpler Taube aircraft at Tsingtao, which the Japanese rebuilt as the Isobe Kaizo Rumpler Taube, as well as an LVG, known to the Japanese as the Seishiki-1, in 1916.