Mexican War of Independence
Although Mexico gained its independence in September 1821, the marking of this historical event did not take hold immediately. The choice of date to celebrate was problematic, because Iturbide, who achieved independence from Spain, was rapidly created Emperor of Mexico. His short-lived reign from 1821–22 ended when he was forced by the military to abdicate. This was a rocky start for the new nation, which made celebrating independence on the anniversary of Iturbide's Army of the Three Guarantees marching into Mexico City in triumph a less than perfect day for those who had opposed him. Celebrations of independence during his reign were marked on September 27. Following his ouster, there were calls to commemorate Mexican independence along the lines that the United States celebrated in grand style its Independence Day on July 4. The creation of a committee of powerful men to mark independence celebrations, the "Junta Patriótica", organized celebrations of both September 16, to commemorate Hidalgo's grito and the start of the independence insurgency, and September 27, to celebrate actual political independence.
History of Monterrey
After the country's independence from the Spanish Crown and the foundation of Mexico in 1821, the governments of Mexico and the United States fought the Mexican-American War, which resulted in the loss of more than half of Mexico's national territory. On 23 September 1846 General William J. Worth besieged the city and a battle between the two countries was fought from Cerro del Obispado to the Villa de Guadalupe, known as the Battle of Monterrey. American troops remained in the Mexican territory until 1848 and the Mexico-American War ended with the treaty of Guadalupe Hidalgo in which the conflicting parties agreed that the United States would acquire the territories of Alta California and New Mexico, and the territory between the Nueces River and the Rio Grande, claimed by the Republic of Texas.