The dawn of the 19th century brought an era of profound transformation to the Americas, none more dramatic than the **Mexican War of Independence**, known in Spanish as the Guerra de Independencia de México. Spanning just over a decade, from September 16, 1810, to September 27, 1821, this momentous armed conflict and intricate political process ultimately severed New Spain's centuries-long ties with its colonial master, Spain, giving birth to an independent nation. Far from a singular, unified rebellion, it was a complex tapestry woven from countless local and regional struggles, often characterized as a revolutionary civil war, deeply influenced by external events and internal social dynamics.

The Long Road to Freedom: Mexico's War of Independence

Understanding the independence movement requires looking beyond a simple cause-and-effect narrative. Mexico's freedom was not an predetermined outcome, but rather a dynamic process shaped by events transpiring across the Atlantic, particularly in Spain itself. These external forces ignited and sustained the armed insurgency that defined the period, creating a fertile ground for change within the vast territories of New Spain.

Roots of Rebellion: A Continent in Crisis

The precipitating event for the **Mexican War of Independence** was an unexpected upheaval in Europe: Napoleon Bonaparte's invasion of Spain in 1808. This audacious move saw the French emperor depose the legitimate Spanish monarch, Charles IV, and install his own brother, Joseph Bonaparte, on the throne. This act triggered an immediate crisis of legitimacy for crown rule throughout the Spanish Empire. In response, both in Spain and its overseas possessions, local provisional governing bodies known as juntas were established, ostensibly ruling in the name of the deposed Bourbon monarchy. A pivotal assembly, the Cortes of Cádiz, gathered in Cádiz, Spain (one of the few areas still under Spanish control), and drafted the groundbreaking Spanish Constitution of 1812. This constitution represented a radical attempt to forge a new governmental framework in the absence of a recognized Spanish monarch, notably seeking to address the long-simmering aspirations of American-born Spaniards, or Creoles, for greater local autonomy and equal status with their Peninsular-born counterparts, the Peninsulares. These political developments had profound and lasting repercussions throughout New Spain, influencing the independence period and the subsequent trajectory of the newly formed nation.

Beneath this political surface, New Spain was already a society marked by deep pre-existing cultural, religious, and racial divides. These divisions played a critical role not only in the initial formation of the independence movement but also in shaping the conflict as it evolved. In September 1808, just two years before the famous Cry of Dolores, Peninsular-born Spaniards in New Spain took matters into their own hands, overthrowing Viceroy José de Iturrigaray (who had been appointed prior to the French invasion). This demonstrated the increasing instability and competing loyalties within the colonial administration.

The Cry of Dolores: Sparking the Insurgency (1810-1814)

The true armed insurgency for **Mexico's independence** began in earnest in 1810. American-born Spaniards, emboldened by the political vacuum and the ideas of self-governance, started to plot an uprising against Spanish rule. The momentous event occurred on September 16, 1810, when Miguel Hidalgo y Costilla, the charismatic parish priest of the small village of Dolores, issued his iconic call to arms – the **Cry of Dolores** (Grito de Dolores). This powerful proclamation galvanized a diverse segment of society, including Indigenous peoples, mestizos, and Creoles, marking the official commencement of the **Mexican War of Independence**. The colonial regime was taken by surprise, largely underestimating the sheer scale and tenacity of the insurgency, which rapidly spread from the fertile Bajío region north of Mexico City to the Pacific and Gulf Coasts, engulfing vast territories in a struggle that would last for over a decade.

Shifting Allegiances: From Absolutism to Independence (1814-1820)

The European theater continued to cast its long shadow over New Spain. With Napoleon's ultimate defeat, Ferdinand VII was restored to the Spanish throne in 1814. His return, however, was a step backward for liberal aspirations. He promptly repudiated the progressive Spanish Constitution of 1812, which had offered a glimmer of hope for greater colonial representation, and instead reinstated absolutist rule. This move rekindled the flames of discontent in New Spain. The struggle continued, with figures like José María Morelos y Pavón taking up the mantle after Hidalgo's capture and execution, continuing the fight for a truly independent nation.

A critical shift occurred in 1820 when Spanish liberals, weary of Ferdinand VII's autocratic style, staged a successful revolt, forcing the king to reinstate the Constitution of 1812. Paradoxically, this turn of events in Spain propelled the final push for independence in New Spain. Many conservatives in the colony, including former royalists, now saw political independence as the only way to safeguard their traditional privileges and maintain the existing social order, which they feared would be threatened by the liberal constitution's potential reforms. This unlikely alliance between former royalist elements and long-standing insurgents proved decisive.

The Plan of Iguala and the Triumph of Three Guarantees (1821)

In a remarkable convergence of interests, these disparate factions came together under the leadership of Agustín de Iturbide, a former royalist officer, and Vicente Guerrero, a seasoned insurgent leader. Together, they forged the **Plan of Iguala**, a revolutionary proclamation that masterfully united diverse segments of society under a common vision. To defend these ideals, they formed the **Army of the Three Guarantees** (Ejército Trigarante), symbolizing the three core tenets of their plan: independence from Spain, the establishment of Roman Catholicism as the sole religion, and equality for all social classes, particularly between Peninsulares and Creoles. This new momentum proved irresistible, leading to the rapid collapse of the royal government in Mexico. The culmination came on August 24, 1821, when Iturbide and Spanish Viceroy Juan O'Donojú signed the **Treaty of Córdoba** in Veracruz, officially ratifying the **Plan of Iguala** and irrevocably confirming **Mexico's independence**.

A New Nation Emerges: Empire, Republic, and Recognition

With independence secured, the mainland of New Spain was initially organized as the **Mexican Empire**, a short-lived Catholic monarchy with Agustín de Iturbide as its first emperor. However, this ephemeral empire was overthrown in 1823, paving the way for the declaration of a federal republic, which was codified in the Constitution of 1824. While Mexico had declared its independence, Spain's official recognition took longer. After several attempts at reconquest, including Isidro Barradas's expedition in 1829, Spain, under the rule of Isabella II, finally acknowledged the independence of Mexico in 1836, bringing a formal end to the colonial chapter and marking the definitive birth of an independent Mexican nation.

Understanding the Plan of Iguala: A Foundational Document

The **Plan of Iguala**, also known as "The Plan of the Three Guarantees" (Plan Trigarante) or sometimes as the "Act of Independence of North America," was a pivotal revolutionary proclamation promulgated on February 24, 1821. It emerged during the final, decisive stage of the **Mexican War of Independence** from Spain and served as the foundational document for the nascent independent nation. This visionary plan articulated Mexico's future as a constitutional monarchy, a compromise that appealed to both conservative and liberal factions. It firmly established Roman Catholicism as the nation's sole official religion, a deeply held belief across society, and crucially, it declared that both Peninsulares and Creoles within Mexico would enjoy equal political and social rights, addressing a long-standing source of colonial grievance. The plan derived its name from the city of Iguala, situated in the modern-day state of Guerrero, where it was first proclaimed. The two towering figures behind its conception and successful implementation were **Agustín de Iturbide**, who would briefly ascend to become the first Emperor of Mexico, and **Vicente Guerrero**, a tenacious revolutionary rebel leader who would later serve as President of Mexico. Their unified forces, dedicated to upholding the ideals enshrined in the Plan of Iguala, formed the formidable **Army of the Three Guarantees**. The plan's tenets were given international legal weight on August 24, 1821, when Iturbide and the last Spanish Viceroy, Juan O'Donojú, signed the **Treaty of Córdoba** in Córdoba, Veracruz, thereby ratifying the Plan of Iguala and cementing **Mexico's independence**. A testament to its innovative and compromising nature, the Plan of Iguala introduced new political concepts while also preserving certain existing rights. Notably, while it established a completely new national army, it upheld the constitutional right of all males to vote regardless of their origin, race, or economic standing – a progressive provision that had been enshrined in the Spanish Constitution of 1812 and was actively in force at the time the Plan was promulgated.

Frequently Asked Questions About the Mexican War of Independence

What was the Mexican War of Independence?

It was an armed conflict and political process that led to Mexico's independence from Spain, lasting from September 16, 1810, to September 27, 1821. It was not a single event but a series of interconnected local and regional struggles.

When did the Mexican War of Independence begin and end?

It officially began on September 16, 1810, with Miguel Hidalgo y Costilla's "Cry of Dolores," and concluded on September 27, 1821, when the **Army of the Three Guarantees** entered Mexico City and the **Treaty of Córdoba** was signed.

Who were the key figures in the Mexican War of Independence?

Prominent figures include Miguel Hidalgo y Costilla (who initiated the revolt), José María Morelos y Pavón (a crucial military leader), Agustín de Iturbide (a former royalist who later championed independence and became emperor), and Vicente Guerrero (a long-time insurgent leader and later president).

What was the "Cry of Dolores"?

The **Cry of Dolores** (Grito de Dolores) was the call to arms issued by Father Miguel Hidalgo y Costilla on September 16, 1810, in the town of Dolores, sparking the **Mexican War of Independence**.

What was the Plan of Iguala?

The **Plan of Iguala**, promulgated on February 24, 1821, was a revolutionary proclamation that outlined the terms for Mexico's independence. It proposed a constitutional monarchy, Roman Catholicism as the official religion, and equality for Peninsulares and Creoles. It was central to the final phase of the independence movement.

What was the Treaty of Córdoba?

Signed on August 24, 1821, by Agustín de Iturbide and Spanish Viceroy Juan O'Donojú, the **Treaty of Córdoba** officially ratified the **Plan of Iguala** and recognized **Mexico's independence** from Spain, effectively ending the war.

How did events in Spain influence Mexican independence?

Napoleon's invasion of Spain in 1808 created a crisis of legitimacy for Spanish rule, leading to the formation of juntas and the drafting of the Spanish Constitution of 1812. Later, a liberal revolt in Spain in 1820 inadvertently pushed conservatives in New Spain to support independence as a way to maintain their status.

When did Spain finally recognize Mexico's independence?

Although independence was declared in 1821, Spain officially recognized **Mexico's independence** much later, in 1836, under the rule of Queen Isabella II, after several attempts at reconquest.