Kowloon Walled City (Chinese: 九龍寨城) was an extremely densely populated and largely lawless enclave within the boundaries of Kowloon City, British Hong Kong. Built as an imperial Chinese military fort, the walled city became a de jure enclave after the New Territories were leased to the United Kingdom in 1898. Its population increased dramatically after the end of the Japanese occupation of Hong Kong during World War II, attracting mostly refugees fleeing the renewed Chinese Civil War.