Hong Kong became a colony of the British Empire at the end of the First Opium War in 1842. Sovereignty over the territory was transferred to China in 1997. As a special administrative region, Hong Kong maintains governing and economic systems that are separate from those of mainland China and its people tend to identify as Hongkongers rather than Chinese, so when China decides to take more control over Hong Kong, the citizenry was understandably upset and took a stand against their overseers.