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.
Mexican War of Independence
During the Díaz regime (1876–1911), the president's birthday coincided with the September 15/16 celebration of independence. The largest celebrations took place and continue to do so in the capital's main square, the zócalo, with the pealing of the Metropolitan Cathedral of Mexico City's bells. In the 1880s, government officials attempted to move the bell that Hidalgo rang in 1810 to gather parishioners in Dolores for what became his famous "grito". Initially the pueblo's officials said the bell no longer existed, but in 1896, the bell, known as the Bell of San José, was taken to the capital. It was renamed the "Bell of Independence" and ritually rung by Díaz. It is now an integral part of Independence Day festivities.