As part of efforts to explore overland trade routes between British India and China's provinces, junior British diplomat Augustus Raymond Margary was sent from Shanghai through southwest China to Bhamo in Upper Burma, where he was supposed to meet Colonel Horace Browne. It took Margary six months to make the 1,800-mile (2,900 km) journey through the provinces of Sichuan, Guizhou and Yunnan and he met Brown in Bhamo in late 1874. On the journey back to Shanghai, Margary heard rumors that the return route was not safe and changed the route to Tengyue. However, he did not notify local officials of their arrivals and confronted native people. In a following conflict on 21 February 1875, he and his four Chinese personal staff were killed.
The incident created a diplomatic crisis and gave British authorities an excuse to put pressure on the Qing government. The crisis was only resolved in 1876 when Thomas Wade and Li Hongzhang signed the Chefoo Convention, which covered a number of items unrelated to the incident.
- Correspondence Respecting the Attack on the Indian Expedition to Western China, and the Murder of Mr. Margary. Chinese Materials Center. 1876. pp. 46–.
- Great Britain. Parliament. House of Commons (1876). Parliamentary Papers, House of Commons and Command. H.M. Stationery Office. pp. 4–.
- Great Britain. Parliament. House of Commons (1877). Accounts and Papers of the House of Commons. Ordered to be printed. pp. 1–.
- John Anderson (1876). Mandalay to Momien: A Narrative of the Two Expeditions to Western China of 1868 and 1875, Under Colonel Edward B. Sladen and Colonel Horace Browne. Macmillan. pp. 417–.
- Thomas Humphry Ward (1885). Men of the Reign: A Biographical Dictionary of Eminent Persons of British and Colonial Birth who Have Died During the Reign of Queen Victoria; Ed. by Thomas Humphry Ward. G. Routledge and sons. pp. 600–.The British Quarterly Review. L. Scott Publishing Company. 1876. pp. 261–.
- Margary, Augustus Raymond, and Rutherford Alcock. The Journey of Augustus Raymond Margary, from Shanghae to Bhamo, and Back to Manwyne: From His Journals and Letters, with a Brief Biographical Preface. London: Macmillan and co., 1876.
- Wang, Shên-tsu. The Margary Affair and the Chefoo Agreement. London, New York: Oxford University Press, 1940.