At the turn of the 19% century, Mexico wanted to create a sovereign government that would act on behalf of their own interests much like the movement for American independence from British rule in the late 18th century. This meant that Mexico no longer wanted to be under Spanish colonial powers.

On 16 September 1810, a Catholic priest by the name of Miguel Hidalgo rang the church bells which called Mexicans to arm against the Spanish. This was the start of the Mexican War of Independence which lasted 11 years, 1 week and 4 days. When the war was over, the first Mexican Empire was established and a declaration of independence was signed. With that, Spain lost the continental area Viceroyalty of New Spain except for the port of San Juan de Ulda. The Viceroyalty of New Spain in this case consisted of Mexico, Central America north of Panama and the southwestern United States.
Mexican Independence Day is celebrated on 16 September.