Peninsular War: A combined Franco-Polish force defeats the Spanish in the Battle of Ciudad Real.

The Peninsular War, a brutal and pivotal military conflict that engulfed the Iberian Peninsula between 1807 and 1814, stands as a defining chapter in the broader narrative of the Napoleonic Wars. It pitted the combined forces of Spain, Portugal, and the United Kingdom against the formidable invading and occupying armies of Napoleon Bonaparte's First French Empire. For Spain, this period is often considered synonymous with its own fiercely fought War of Independence, a desperate struggle for sovereignty that left an indelible mark on its national consciousness.

The Seeds of Conflict and French Occupation

The war's origins trace back to 1807, when French and Spanish armies initially allied to invade and occupy Portugal, with French troops transiting through Spain. However, the situation dramatically escalated in 1808. Napoleonic France, having been an ally, turned its focus squarely on Spain itself. In a calculated and audacious move, Napoleon Bonaparte orchestrated the forced abdications of the Spanish King Charles IV and his son, Ferdinand VII. He then installed his own brother, Joseph Bonaparte, on the Spanish throne and promulgated the controversial Bayonne Constitution. This act of foreign imposition was met with widespread indignation and outright rejection by most Spaniards, who were unwilling to accept French rule without a fight. What followed was a bloody and protracted conflict aimed at expelling the occupiers.

The Birth of Resistance: Dos de Mayo and Guerrilla Warfare

The flame of Spanish resistance ignited dramatically with the iconic Dos de Mayo Uprising on May 2, 1808, in Madrid. This spontaneous, violent popular revolt against the French occupation signaled the true beginning of the war within Spain. The French invasion had shattered the existing Spanish administration, leading to its fragmentation into numerous, often quarreling, provincial juntas. Despite the initial disarray, these juntas became localized centers of resistance. A reconstituted national government, the Cortes of Cádiz – effectively a government-in-exile – fortified itself in the secure port city of Cádiz in 1810. Although besieged by some 70,000 French troops, the Cortes managed to promulgate the liberal Spanish Constitution of 1812, a foundational document that would later become a cornerstone of European liberalism. The conflict is also profoundly significant for being one of the first wars of national liberation and, crucially, for the emergence of large-scale guerrilla warfare. Spanish armies, though repeatedly beaten and driven to the peripheries, would regroup and relentlessly harass and demoralize French troops. These partisan fighters, employing raids and ambushes, tied down vast numbers of Napoleon's forces, constantly challenging French control of territory and communications. Napoleon himself, vexed by the endless drain on his resources, famously dubbed the conflict the "Spanish Ulcer."

The Allied Effort: Britain, Portugal, and the Turning Tide

While Spain grappled with internal divisions and fierce partisan warfare, British and Portuguese forces played a crucial role. They eventually secured Portugal, transforming it into a vital base of operations from which to launch campaigns against the French army in Spain. From this safe position, they also supplied what they could to their Spanish allies. The demoralized Portuguese army underwent a significant reorganization and refit under the command of General William Beresford, who had been appointed commander-in-chief by the exiled Portuguese royal family. This reformed force then fought alongside the British as part of the combined Anglo-Portuguese Army under the brilliant leadership of then Lt. Gen. Sir Arthur Wellesley, who would later become the 1st Duke of Wellington. The combined allied forces, both regular armies and irregular guerrillas, restricted French territorial control and prevented Napoleon's marshals from fully subduing the rebellious Spanish provinces, leading to years of costly stalemate.

Wellington's Victories and the French Retreat

The strategic landscape shifted dramatically in 1812 when Napoleon embarked on his disastrous invasion of Russia with a massive army, drawing crucial resources away from the Iberian Peninsula. Seizing this opportunity, a combined allied army under Wellesley pushed deep into Spain, achieving a decisive victory over the French at Salamanca and subsequently capturing the capital, Madrid. The following year, Wellesley scored another monumental triumph, routing King Joseph Bonaparte's army in the pivotal Battle of Vitoria. Pursued relentlessly by the combined armies of Britain, Spain, and Portugal, Marshal Jean-de-Dieu Soult, facing dwindling support from a depleted France, led his exhausted and demoralized French forces in a fighting withdrawal across the formidable Pyrenees mountains during the harsh winter of 1813–1814. The Peninsular War officially concluded on April 17, 1814, with the restoration of Ferdinand VII to the Spanish monarchy, coinciding with Napoleon's ultimate defeat by the Sixth Coalition.

Lasting Impact and Legacy

The years of fighting in Spain imposed an immense burden on France's Grande Armée. Despite often winning individual battles, the French were ultimately defeated by the relentless attrition, severely tested communications and supply lines, and the constant harassment from partisans. Their units were frequently isolated or overwhelmed by the intense guerrilla war of raids and ambushes. The cumulative crises and disruptions of invasion, revolution, and restoration utterly destroyed the social and economic fabric of both Portugal and Spain. The war ushered in an era of profound social turbulence, increased political instability, and prolonged economic stagnation. Devastating civil wars between liberal and absolutist factions, often led by officers who had gained experience during the Peninsular War, plagued Iberia until the mid-19th century. Furthermore, the war's destabilizing effects were a major catalyst for the independence movements across most of Spain's American colonies and the eventual independence of Brazil, which remained a monarchy after severing its ties with Portugal. One notable engagement amidst this broader conflict was the Battle of Ciudad Real, fought on March 27, 1809, which resulted in a French victory under General Sebastiani against the Spanish forces led by General Conde de Cartojal.

Frequently Asked Questions about the Peninsular War

What was the Peninsular War?
The Peninsular War was a military conflict fought in the Iberian Peninsula (Spain and Portugal) from 1807 to 1814, primarily between the First French Empire and allied forces of Spain, Portugal, and the United Kingdom. It was a major component of the broader Napoleonic Wars.
When did the Peninsular War take place?
The war lasted from 1807 to 1814, officially concluding on April 17, 1814.
Who were the main combatants in the Peninsular War?
The primary belligerents were Napoleon's First French Empire against an alliance of Spain, Portugal, and the United Kingdom.
What caused the Peninsular War?
The war began with the French and Spanish invasion of Portugal in 1807, but escalated significantly in 1808 when Napoleon occupied Spain, forced the abdication of the Spanish monarchy, and installed his brother Joseph Bonaparte on the throne. This sparked widespread Spanish resistance.
What was the significance of the Peninsular War?
It is considered one of the first wars of national liberation and is notable for the emergence of large-scale guerrilla warfare. It drained vast French resources, which Napoleon famously called the "Spanish Ulcer," contributing to his eventual downfall. The war also led to the liberal Spanish Constitution of 1812 and profoundly impacted the independence movements in Spanish American colonies and Brazil.
Who was Arthur Wellesley?
Arthur Wellesley, later the 1st Duke of Wellington, was the British general who commanded the combined Anglo-Portuguese forces throughout much of the Peninsular War. His strategic brilliance and leadership were crucial to the allied victory over the French.
What was the "Spanish Ulcer"?
The "Spanish Ulcer" was a term coined by Napoleon Bonaparte himself to describe the Peninsular War. It reflected his frustration over the continuous drain of French resources, manpower, and morale due to the relentless guerrilla warfare and sustained resistance from the Spanish, Portuguese, and British forces, which severely hampered his overall war efforts.