One cannot fully understand Beijing’s long strategy over Hong Kong without considering China’s imperial legacy of stepwise absorption and assimilation of its ethnic frontiers and the history of the CCP’s struggle to control these frontiers in the early years of the PRC. Chapter Five outlines the development of the ideas and experiments of “One Country, Two Systems” before Hong Kong, analyzing the CCP’s attempt to absorb and assimilate its ethnic frontiers such as Tibet since the 1950s. Beijing’s leaders explicitly referenced these histories, in particular the history of Tibet in 1951-59, when they first devised and promoted the “One Country, Two Systems” formula in the early 1980s as a solution to the Hong Kong question.