Established in 1877, The Chinese Embassy in the United Kingdom (former Chinese Legation) is the first diplomatic mission abroad in the history of China.
After the Opium War, Britain intensified its exploitation of China. Having occupiedMyanmar, Britian increasingly keen to make forays into Southwest China and attempted to open a route from Myanmar to China's southwester frontier Yunnan, , before reaching the hinterland of China. In 1874, the British government commissioned an exploring team of over 200 people, led by Horace Browne, to enter into Yunnan from Myanmar to survey the terrain and traffic conditions in that area. The British Minister to China Thomas Wade sent interpreter Augustus Raymond Margary to China-Myanmar border to meet the team. Margary set off in Shanghai, travelling through provinces of Hubei, Hunan, Guizhou and Yunnan and arrived at Bhamo in Myanmar on January 17, 1875, to meet with the exploring team. In January 19, Margary led the team to Yunnan. On January 22, they were caught in a conflict with local people on their way to Tengyue. Margary was killed and Browne and others were forced back to Bhamo. This was the sensational"Margary Affair", or "Dian Affair". It prompted the Qing government to establish diplomatic missions abroad.
The British government seized upon the incident to blackmail and put pressure on the Qing government , seeking greater exploitation of China. Under the pressure of the British government, the Qing government had to sign on September 13, 1876 the unequal treaty to settle the "Margary Affair" – the Chefoo Convention. The Convention contained 16 articles in three parts, one of which obliging China to pay 200,000 taels of silver in indemnities to compensate the victims' families and reimburse the British government of the costs incurred to settle the case. China must send an imperial envoy to Britian to make an apology to the British Queen. Due to the pressure from the British side and considerations on the needs of foreign relations, the Qing government decided to send Guo Songtao, the then Fujian Provincial Surveillance Commissioner (按察使 Anchashi), who advocated Westernization reforms and was known as being proficient in foreign affairs, to Britian to "apologize" and establish the post of Minister to Britain, and appointed Liu Xihong as Vice Minister.
On December 2, 1876, Guo Songtao and other more than 30 people, including his wife Liang, Vice-Minister Liu Xihong, Counsellor Li Shuchang, Interpreter Fung Yi, De Ming and Halliday Macartney (British, who later was promoted to Counsellor of the Chinese Legation in the UK and was knighted by Queen Victoria. He masterminded the entrapping of Sun Yat-sen inthe Chinese Legation in 1896), departed by boat from Shanghai, arrived on January 21, 1877 at Southampton, a port city in southern Britain, and then took train to London. Before Guo and his party arrived in Britain, Scottish James Duncan, the then Director of London Office of the Chinese Customs Service, had rented Portland Avenue 49.Upon arrival in London, Guo and his party stayed in this five-story building constructed 100 years ago. In February 7, Guo had an audience with Queen Victoria, in which he made a formal apology on the Margary Affair and presented his credentials to become the first Chinese diplomatic envoy. He held the office for 3 years and 2 months.49 Portland thus became the premises of China's first diplomatic mission in the history - the Chinese Legation (later Chinese Embassy), and has been in use ever since.