Fantastic War

Background

When the Seven Years' War between France and Great Britain started in 1756, Spain and Portugal remained neutral. Their differences in South America had been settled by the Treaty of Madrid (1750). King Ferdinand VI of Spain's prime minister Ricardo Wall opposed the French party who wanted to enter the war on the side of France.

Everything changed when Ferdinand VI died in 1759 and was succeeded by his younger half-brother Charles III of Spain. Charles was more ambitious than his melancholic brother. One of the main objects of Charles's policy was the survival of Spain as a colonial power and, therefore, as a power to be reckoned with in Europe.

By 1761 France looked like losing the war against Great Britain. Furthermore, Spain suffered from attacks by English privateers in Spanish waters, and claimed compensation. Fearing that a British victory over France in the Seven Years' War would upset the balance of colonial power, he signed the Family Compact with France (both countries were ruled by branches of the Bourbon family) in August 1761. This brought war with Great Britain in January 1762.

After Portugal had been struck by the disastrous 1755 Lisbon earthquake, Prime Minister Sebastião José de Carvalho e Melo, Marquis of Pombal directed all efforts towards the reconstruction of the country, and neglected the armed forces, for which he had little interest anyhow. By the Treaty of El Pardo (1761) between Spain and Portugal, all aspects of the Treaty of Madrid were null and void.

War

Spain agreed with France to attack Portugal which remained neutral, but which was an important economical ally of Great Britain. France hoped that this new front would draw away British forces, now directed against France.

The triple Franco-Spanish invasion of Portugal in Europe (main theater of the war, which absorbed the lion's share of the Spanish war effort), on 5 May 1762, was followed by a Spanish invasion of Portuguese territories in South America (a secondary theater of the war). While the first ended in humiliating defeat, the second represented a stalemate: Portuguese victory in Northern and Western Brazil; Spanish victory in Southern Brazil and Uruguay.

Peninsular action (main theater)

During the war, a Franco Spanish army of about 42,000 men, first led by the Marquis of Sarria and then by the Count of Aranda, invaded Portugal in 1762, at three different regions in three different times: provinces of Trás-os-Montes (first invasion of Portugal, May–June 1762), province of Beira (second invasion of Portugal, July–November 1762) and Alentejo (third invasion, November 1762). They were faced by ferocious popular resistance and, from the middle of the second invasion onwards, by a tiny Anglo-Portuguese army of nearly 15,000 men superiorly commanded by the Count La Lippe.

In the first invasion, the Spaniards – whose final goal was Oporto, the second city of the Kingdom- occupied without any opposition several undefended towns and ruined fortresses of the Province of Trás-os-Montes (there were neither regular soldiers nor powder in the entire province, except in the fortress of Miranda do Douro).

The guerrillas exploited the mountainous nature of the province to cut off the Bourbon’s supply and communication lines with Spain as well as to inflict heavy losses on the invaders. The populations abandoned their villages inducing famine among the Spaniards, who launched two offensives towards Oporto: the first was defeated by the militia and peasants at the battle of Douro and the second was beaten off at the Mountains of Montalegre.

This failure and the arriving of Portuguese reinforcements (including regular troops) forced the now diminished Spanish army to retreat into Spain, abandoning all their conquests (except Chaves). After this defeat, the Franco-Spanish commander, Sarria, was replaced by Count of Aranda.

During this first invasion of Portugal, the total Spanish casualties, according to a contemporaneous French source, general Dumouriez, were 10,000 men: prisoners, deserters or deaths by hunger, guerrilla’s ambushes and disease (8,000 according to modern Spanish military historian José Luis Terrón Ponce).

At the request of Portugal, one British force of 7,107 soldiers and officers landed in Lisbon, deeply reorganizing the Portuguese army (7 to 8.000 regular soldiers). The supreme command of the allied army (from 14 to 15.000 men) was delivered to one of the best soldiers of his time: the Count of Lippe.

In the beginning of the second invasion (province of Lower Beira, July–November 1762), the Franco-Spaniards were successful and took several poorly equipped Portuguese fortresses and towns, including Almeida. However, the Anglo-Portuguese army defeated a Spanish corps who was preparing another invasion through the province of Alentejo (battle of Valencia de Alcántara) and avoided the Spanish attempt of crossing the river Tagus, defeating them at Vila Velha.

The allied army eventually stopped the Bourbon army’s march toward Lisbon in the mountains near Abrantes (which by its position dominated the country) and used a scorched earth strategy -in cooperation with the rural population- to starve the invaders: peasants abandoned their villages, destroying or taking with them all the food, while the guerrillas attacked their logistic lines. The invaders had to choose between stay and starve or withdraw.

The outcome was the destruction of the Franco-Spanish army, whose remnants – leaving their wounded and sick behind- were chased to Spain by the Anglo-Portuguese army and peasants, after two encirclement movements delineated by a Portuguese force under general Townshend toward the enemy´s rear: the first move forced the Bourbons to withdraw from the hills east of Abrantes to Castelo Branco, while the second made them flee to Spain. The Spanish headquarters (Castelo Branco), was captured by the Allied army who thus made thousands of prisoners (2 November 1762).

"The region was devastated, there were no provisions... The burning of villages punished the vengeance of the inhabitants; but these punishments only made crueler the fate of the Spanish armies.
Then the small Anglo-Portuguese army took the offensive. The Count of Lippe gave the order to attack. Loudon [in reality it was Townshend] was ordered to join the troops of General Lennox and to place himself between Almeida and Badajoz. This way, the line of retreat of the Aranda´s army... would be threatened. Aranda [immobilized by the excellent Anglo-Portuguese defensive positions in the mountains near Abrantes] was forced to choose between withdrawing or starve to death in Beira. (...). General Loudon [Townshend] managed to occupy Fundão, making the Spanish advanced guards withdraw. The Spanish army retreats [towards Castelo Branco, closer to the Spanish border], and the Portuguese troops advance, reoccupying Vila Velha, and the Loudon [Townshend]’s force recovers Penamacor and Monsanto; while another officer, Field Marshal Frazer, chased the enemy with two battalions and four cavalry regiments.
Then, taking advantage of the disorder caused by the withdrawal, The Count of Lippe outlined a plan that would imprison Aranda and all his army in Castelo Branco [The Spanish headquarters]. Bad weather delayed the operation and an informer reported the Spanish commander about the intentions of Lippe. The Spanish army hastily retreated to his own country. The last enemy troops withdrew ... and shortly after, the Portuguese occupied again the border posts with the exception of Chaves and Almeida ...",

The total Franco-Spanish losses in this second invasion were evaluated by a contemporaneous Bourbon source as 15,000 men (Dumouriez in 1766), while the total casualties for both the invasions were about 30, 000 men, according to the British ambassador in Portugal, Eduard Hay (8 November 1762).

As explained by Historians Danley Mark and Patrick Speelman:

"... Bourbon casualties mounted because the Portuguese peasantry waged a relentless war of revenge against deserters and retreating soldiers who they captured and massacred in large numbers (p. 452)....The Portuguese campaign, indeed the entire Spanish war, lay in ruins (p. 521)."

During the third Spanish offensive (November, 1762), the Spaniards attack by surprise two Portuguese towns (Ouguela and Marvão) - but were defeated - and had to retreat again before the reinforced and advancing Anglo-Portuguese army who took some prisoners. Additional Spanish prisoners were taken when a Portuguese force led by British Colonel Wrey entered Spain and attacked the region of Codicera (19 November).

Thus, Aranda, with his forces ruined and demoralized, sent to Lippe an emissary proposing an armistice (24 November), which was accepted and signed on 1 December 1762.

South America (secondary theater)

In South America, the Spanish Cevallos expedition (3,900 men) was more successful. In present-day Uruguay, they captured Colónia do Sacramento (with 767 defenders), and two other fortresses: fort of Santa Teresa (with 400 defenders), on 19 April 1763; and fort of San Miguel (with 30 defenders), in April 23.

Cevallos advanced and won a still greater victory when he conquered most of the vast and rich territory of the so-called “S.Peter´s Continent” - the present day Brazilian state of Rio Grande do Sul where the Portuguese had only up to 1,000 men (soldiers and militia). São José do Norte and the capital – S. Pedro do Sul- were abandoned without a fight. However, the Spaniards were routed by the Portuguese in the battle of Santa Bárbara (1 January 1763), when an invading army of 500 Spaniards and 2,000 Indians, in cooperation with Cevallos, tried to conquer Rio Pardo, nearly the only remaining Portuguese territory in Rio Grande do Sul: seven cannons, 9,000 heads of cattle and 5,000 horses were captured. This huge territory would be completely retaken by the Portuguese during the so-called “deaf war” (1763-1777).

A Spanish army of 600 or 1200 men (according to the sources) tried to retake the territory of Mato Grosso, in the right bank of the Guaporé River, besieging the fortress of Conceição (the “door” for the gold-rich Province of Mato Grosso). The 100 defenders, after receiving reinforcements, not only resisted but conquered and occupied – until the end of the war – the reductions of S. Miguel and S. Martin, which were main sources of Spanish supply and were located on the Spanish side of the river Guaporé (left bank). They also used biological warfare. The Spaniards withdrew – after losing half of their men from hunger, disease and desertion – leaving the Portuguese in the possession of the disputed territory. Rolim Moura was rewarded with the vice-royalty of Brazil for this victory.

The Portuguese conquered most of the valley of Rio Negro, expelling the Spaniards from S. Gabriel and S. josé de Maribatanas (1763) and building two fortresses there with the Spanish cannons.

Aftermath

In the Treaty of Paris (1763) the status quo between Spain and Portugal of before the war was restored:

Europe

Spain was forced to return to Portugal the small cities of Almeida and Chaves on the Hispano-Portuguese frontier. All the other cities and strongholds had been retaken by the Anglo-Portuguese army during the chase of the remnants of the Franco-Spanish troops.

South America

The Spanish-Portuguese colonial conflict during the Seven Years' War ended in a tactical stalemate, but it would represent a Portuguese strategic victory in the short run. Except for the forts of Santa Teresa and San Miguel, the Spaniards would lose to the Portuguese all the territory conquered during the war. Colonia do Sacramento was given back by the same Treaty of Paris, which ended the war, and Rio Grande do Sul would be retaken from the Spanish army during the undeclared war of 1763-1777, and Portugal retained all its conquests (Rio Negro Valley and Guaporé River’s right bank/Mato Grosso).