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The Unequal Treaty of 1842 forced China to open 5 ports to foreign trade, pay the British, and give Britain Hong Kong Island. The Treaty of Tianjin, signed after the second Opium War, resulted in 10 more open ports, permitted travel through the interior, money for Britain and France, and Britain, America, French, and the Russians were all allowed to install legations in Beijing. The Treaty of Aigun, also signed after the second Opium War, did this.
What is gave Russia coastal land in northern China?