British Hong Kong was the period during which Hong Kong was under British colonial rule, from 1841 to 1997. The colonial period began with the British occupation of Hong Kong Island on 26 January 1841 during the First Opium War (1839–1842). The island was ceded to the United Kingdom by the Qing dynasty of China on 29 August 1842 and established as a Crown colony on 26 June 1843. It was later designated a British Dependent Territory in 1981. The Kowloon Peninsula was added to the colony after the Second Opium War (1856–1860). Finally, the New Territories were added under a 99-year lease in 1898. Although Hong Kong Island and Kowloon were ceded to Britain in perpetuity, the New Territories – which comprised over 90 per cent of Hong Kong's land – had such a vital role in the economy that the British government agreed to transfer sovereignty of the entirety of Hong Kong to China upon the expiration of the lease in 1997. The transfer has been considered by many as marking the end of the British Empire.