Hong Kong–United Kingdom relations a deeply important role in the formation of the modern Hong Kong. Sovereignty of Hong Kong was ceded to the UK "in perpetuity" on 29 August 1842 through the Treaty of Nanking. The UK further expanded the territory of Hong Kong in 1860 by another cessation, plus a 99-year lease of the New Territories in 1898. The stability, security, and predictability of British law and government enabled Hong Kong to flourish as a centre for international trade. Localisation of teritary institutions, the Hong Kong government and the independent Judiciary in the run-up to the 1997 Handover of sovereignty, caused a
British Hong Kong one of the colony's wealthiest people by this time. During China's turbulent period in the 20th century, Hong Kong served as a safe haven for dissidents, political refugees, and officials who lost power. British policy allowed dissidents to live in Hong Kong as long as they did not break local laws or harm British interests. The implementation of this policy varied according to what the senior officials thought constituted British interests and the state of relations with China. The Canton–Hong Kong strike (1925–1926) was anti-imperialist in nature. The 1966 riots and Maoist-led 1967 riots, essentially spillovers from the Cultural Revolution,