In what year did Mexico finally achieve independence from Spain?

Mexico achieved independence from Spain in 1821 after a prolonged struggle that began with an uprising in 1810. This culmination is significant in Mexican history as it marked the end of over 300 years of colonial rule. The movement for independence was fueled by various social, political, and economic factors, including a desire for self-governance and resistance against oppressive colonial policies.

The year 1810 is notable for the beginning of the fight for independence, marked by the Grito de Dolores, but it was not until 1821 that the conflict resolved with the signing of the Plan of Iguala and the subsequent recognition of independence. Thus, the answer reflecting the culmination of this effort, where Mexico was officially recognized as an independent nation, is clearly 1821.