Spanish attempts to reconquer Mexico
Mexican independence was officially achieved on September 27, 1821, under the Treaty of Córdoba. Spain did not recognize the treaties, arguing that the viceroy Juan O'Donojú had no authority to recognize the independence of any overseas province. This situation was dangerous to the newly acquired independent status of the nation, which had not yet been recognized by any of the European powers that could support it, and the threat of Spanish reconquest was a constant worry to the leaders of the nascent regime. On May 13, 1822 decrees were issued by the government to imprison anyone who conspired against Mexico's independence.
Mexico–United Kingdom relations
After Mexico declared its independence in 1810, Britain was the first European "great power" to recognize Mexican sovereignty. Soon afterwards, Emperor Agustín de Iturbide sent a diplomatic envoy to London to establish diplomatic communications between the two nations. In 1837, both nations signed a treaty to abolish the slave trade. The British established a network of merchant houses in the major cities. However, according to Hilarie J. Heath, the results were bleak: