After a brief historical overview, this chapter looks at how Japan’s modern imperialism and the reference to the imperial system established after the Meiji Restoration (1868), up until the defeat of 1945, have an impact on the Japanese people today. Three points are addressed: the structuring character of this past for Japanese politics; the persistence, in an unofficial way, of the “State Shintō” established during the period of the empire; the reconfigurations of Japanese national identity after 1945 and the place it gives to the post-colonial minorities present in the archipelago. The ruptures and continuities with the period of the empire offer a relevant key to understanding politics, religions and certain aspects of Japanese society. This chapter can be read as an introduction to understanding contemporary Japan.