FACTBOX: The who, what, when and why of the Hong Kong handover

(Reuters) - At midnight on June 30, 1997, Hong Kong was handed back to China, ending 156 years of British rule.

Here are some facts on the history of the handover:

BRITAIN'S 99-YEAR LEASE:

-- Hong Kong was wrested from China by Britain in three phases, starting with the mid-19th century "opium wars".

-- Hong Kong Island went first, under the Treaty of Nanking in 1842. The Kowloon Peninsula followed, in the 1860 Convention of Peking. The rural New Territories, a mainland area adjacent to Kowloon and 235 islands, was added under a 99-year lease in 1898.

-- Under these treaties, the New Territories, which comprise 70 percent of the colony's area, would revert to China in 1997.

TERMS FOR THE HAND-OVER:

-- After two years of negotiations, Margaret Thatcher and the leader of China, Zhao Ziyang, signed the Sino-British Joint Declaration on December 19, 1984.

-- It agreed all of Hong Kong would be returned to China at midnight on June 30, 1997; it guaranteed a 50-year extension of Hong Kong's capitalist system and relative autonomy until 2047 under the "one country, two systems" formula.