The British invasions of the Río de la Plata were a series of unsuccessful British attempts to seize control of the Spanish colonies located around the La Plata Basin in South America (today part of Argentina and Uruguay). The invasions took place between 1806 and 1807, as part of the Napoleonic Wars, when Spain was an ally of France.

The invasions occurred in two phases. A detachment from the British army occupied Buenos Aires for 46 days in 1806 before being expelled. In 1807, a second force occupied Montevideo, remaining for several months, and a third force made a second attempt to take Buenos Aires.

After several days of street-fighting against the local militia and Spanish colonial army, in which half of the British forces were killed or wounded, the British were forced to withdraw.

The social effects of the invasions are among the causes of the May Revolution. The criollos, who had so far been denied the most important works, could get political strength in military roles. The successful resistance with little help from the peninsula fostered the desire of self-determination.

An open cabildo and the Royal Audience of Buenos Aires deposed the viceroy Rafael de Sobremonte and designated instead the popular hero Santiago de Liniers, which was a complete unprecedented action: before that, the viceroy was only subject of the King of Spain himself, and no Spanish American had authority over him.

Background

Pedro de Mendoza founded the Ciudad de Nuestra Señora del Buen Ayre (Our Lady of the Fair Winds) on 2 February 1536 as a Spanish settlement. The site was abandoned in 1541, but re-established in 1580 by Juan de Garay with the name Ciudad de la Santísima Trinidad y Puerto de Santa María del Buen Ayre, and the city became one of the largest in the Americas.

A Portuguese colony was founded nearby at Colonia del Sacramento in 1680. To deter Portuguese expansion, the Spanish founded Montevideo in 1726, and Colonia was finally ceded to Spain under the Treaty of San Ildefonso in 1777, one year after the creation of the Spanish Viceroyalty of the Río de la Plata, the forerunner of modern Argentina.

The South Sea Company was granted trading concessions in South America in the time of Queen Anne, under the Treaty of Utrecht. The British had long harboured ambitions in South America, considering the estuary of the Río de la Plata as the most favourable location for a British colony.

The Napoleonic wars played a key role in the Rio de la Plata conflict. Since the beginning of the conquest of the Americas, England had been interested in the riches of the region.

The Peace of Basel in 1795 ended the war between Spain and France. In 1796, by the Second Treaty of San Ildefonso, Spain joined France in its war with Britain, thus giving Britain cause for military action against Spanish colonies. Britain judged it the right moment after the defeat of the Franco-Spanish fleet at the Battle of Trafalgar.

This battle gave the British complete naval supremacy, and forced Spain to lower the naval communications with its American colonies. Even so, Buenos Aires had been historically neglected by Spain, which preferred to send most of its ships to Lima. The last time when Spanish military bodies arrived to Buenos Aires was in 1784.

British Pretensions

Britain had long harboured interests in taking control of the region before the invasions. Back in 1711, John Pullen stated that the Río de la Plata was the best place in the world for making a British colony. His proposal included Santa Fe and Asunción, and would generate an agriculture area with Buenos Aires as the main port. Admiral Vernon declared as well the benefit of opening markets in those areas in 1741.

By 1780 the British government approved a project of colonel Fullarton to take the Americas with attacks from both the Atlantic (from Europe) and the Pacific (from India). This project was canceled.

Nicholas Vansittart made a new proposal in 1796: the plan was to take Buenos Aires, then move to Chile and attack from there the Spanish stronghold of El Callao in Peru. This proposal was canceled the following year, but was improved by Thomas Maitland in 1800 as the Maitland Plan.

The new plan was to seize control of Buenos Aires with 4.000 soldiers and 1.500 cavalry, move to Mendoza, and prepare a military expedition to cross the Andes and conquer Chile. From there, the British would move from sea to emancipate Perú and then Quito.

All those proposals were discussed in 1804 by William Pitt, lord Henry Melville and sir Home Riggs Popham. Popham did not trust in a complete military occupation of South America, but just in taking control of key locations to allow the main objective, to open new markets for the British economy.

Although there was consensus in weakening the Spanish control over the Spanish colones in South America, it wasn’t agreed the system and moment to take such plans into action. For instance, it was not agreed whenever Britain should turn those cities into British colonies, or promote their emancipation under British protection.

First Invasion

In 1805 Popham received orders to escort the David Baird-led expedition against the Dutch colony of the Cape of Good Hope, which was allied with Napoleon. With nearly 6.300 men they took it in January, 1806.

Popham received new orders from the admiralty to patrol the east coast of South America, from Rio de Janeiro to the Río de la Plata, in order to detect any attempt to counter attack the Cape. However, Popham had the idea of taking the Río de la Plata with a military action similar to the one made at the Cape.

His agent William White had him informed about the local politics of the city, such as the discontent among some groups about the restrictive regulations enforced by Spain about international commerce. Popham manifested Baird his will to take the zone, with or without his help. Baird gave him the 71st Regiment of Infantry, artillery and 1.000 men to attempt the invasion.

Baird promoted William Carr Beresford to general and designated him vicegobernor of the zone if it was taken. The expedition got reinforcements of 1.500 men and 36 officials at Saint Helena.

The Spanish Viceroy, Marquis Rafael de Sobremonte, had asked the Spanish Crown for reinforcements many times, but only received a shipment of several thousand muskets and instructions to form a militia. Buenos Aires was then a large settlement housing approximately 45,000, but the Viceroy was reluctant to give weapons to the Creole population.

The best troops had been dispatched to the Upper Peru and to guard the frontiers with the natives, and when Sobremonte learned of the British presence in the area he dispatched the remaining troops to Montevideo, considering that the attack would be in that city. Thus, the British found Buenos Aires almost defenseless.

The British took Quilmes, near Buenos Aires, on 25 June 1806, and reached and occupied Buenos Aires on the 27 June. The Viceroy fled to Córdoba with the city’s treasury, but lost it to British forces during his escape. Although his action was in line with a law enacted by former Viceroy Pedro de Cevallos, which required the treasury to be kept safe in case of a foreign attack, he was seen as a coward by the population because of it.

The wealthy members of society were pleased with the British arrival. All politicians swore loyalty to them, such as the members of the Cabildo or the Consulates, with the exception of Manuel Belgrano, who fled to the Banda Oriental. Religious leaders swore loyalty as well, after securing the promise that the catholic religion would be respected.

The Real Audience ended its activities. The rich people included the British among their celebrations, and those promised that their slaves wouldn’t be emancipated. However, the bulk of the population did not like the new situation and rejected both the British and the Spanish authorities that had surrendered to them. Merchants were also displeased by the repeal of the Spanish monopoly of commerce and the opening to free trade, as it harmed their interests; one of their leaders was Martín de Álzaga.

Finally, a group of logists led by Juan José Castelli had been told years ago by James Florence Burke (who was actually a spy) about a proposal from Francisco de Miranda to emancipate the Spanish colonies under British protection.

Castelli arranged an interview with Beresford to clarify whenever the British had the intention to follow the mentioned plan; when Beresford refused, they joined the resistance.

de Álzaga organized the digging of a secret tunnel to the fort, where the British were located, with the purpose of filling it with explosives and attacking the invaders by surprise. Juan Martín de Pueyrredón organized a militia near the city, but was discovered before being ready, and his troops were defeated.

Santiago de Liniers, who was assigned to guard a nearby coast defense, got into the city and weighted the situation. He convinced Álzaga to hold on his plan, and moved to Montevideo. The governor Ruiz Huidobro gave him command of 550 veterans and 400 soldiers to return to Buenos Aires and attempt the re-conquest. Sobremonte was doing the same in Córdoba, but Liniers got to Buenos Aires first.

On 4 August 1806, Liniers landed at Las Conchas, north of Buenos Aires, and advanced with a mixed force of Buenos Aires line troops and Montevideo Militia toward the city. On August 10 he took control of the strategic points of Miserere and El Retiro, holding the north and west entries to the city.

Beresford finally surrendered on 14 August. An open cabildo decided afterwards to depose Sobremonte from having military authority, and giving instead such authority to the victorious Liniers.

As pointed, Sobremonte’s departure at the beginning of the war made him highly unpopular among the peoples of Buenos Aires. Sobremonte would not return to Buenos Aires, and move to Montevideo instead. The open cabildo decided as well to prepare the city against the possibility of a British counter-attack.

Foreseeing the possibility of a second invasion, militias were formed by the Spanish and criollos, such as the Patricios, Arribeños, Húsares (of Pueyrredón), Pardos and Morenos. The creation of such local forces created concern within the Spanish elite, fearful of an attempt of secession from the Spanish Crown.

On this first invasion, the 71st Regiment of Foot lost both of its Regimental Colours during the combat, which are currently held in Argentina. On the second invasion, there was a frustrated attempt to recover both flags. They were retaken by the Buenos Aires militia and returned to the Santo Domingo convent. Another two banners from the British Royal Navy are also held in the convent.

Second Invasion

Battle of Montevideo

On 3 February 1807, Montevideo was captured in a joint military and naval operation using British reinforcements of 10,000 men under General Sir Samuel Auchmuty and a naval squadron under Admiral Sir Charles Stirling.

On 10 May, Lieutenant-General John Whitelocke arrived in Montevideo to take overall command of the British forces on the Río de la Plata. He landed on 27 June.

2nd Battle of Buenos Aires

On the 1st of July, the force led by Liniers fought bravely but was overwhelmed by superior numbers in the city environs. At this crucial moment, Whitelocke did not attempt to enter the city, but twice demanded the city’s surrender. Meanwhile, Buenos Aires’ mayor Martín de Álzaga organised the defence of the city by digging trenches, fortifying buildings and erecting fences with great popular support for the Creoles hungered for independence.

Finally, 3 days after forcing the troops under Liniers to retreat, Whitelocke resolved to attack Buenos Aires. Trusting in the superiority of his soldiers, he divided his army into 12 columns and advanced without the protection of the artillery.

His army was met on the streets by a mixed race militia, including 686 African slaves, stiffened by the local 1st Naval Infantry Battalion and 1st ‘Los Patricios’ Infantry Regiment, and fighting continued on the streets of Buenos Aires on 4 July and 5 July.

Whitelocke underestimated the importance of urban combat, in which the inhabitants employed cooking pots filled with burning oil from rooftops, injuring several redcoats of the 88th Regiment. The locals eventually overwhelmed the British troops.

By the end of 5 July, the British controlled Retiro and Residencia at the cost of about 70 officers and 1,000 other ranks killed or wounded, but the city’s centre was still in the hands of the defenders, and the invaders were now demoralized.

At this point, a counter-attack by the creole militias and the elite troops present, defeated many important British commanders, including Robert Crauford and Dennis Pack. Then Whitelocke proposed a 24-hour truce, which was rejected by Liniers, who ordered an artillery attack.

After suffering 311 killed, 679 wounded and 1,808 captured or missing, Whitelocke signed an armistice with Liniers on 12 August; the local marines playing an important part in defeating Brigadier-General Robert Crauford and his two thousand redcoats at the Battle of Plaza del Mercado which is now recalled by the people of Buenos Aires as ‘The Defence’. He left the Río de la Plata basin taking with him the British forces in Buenos Aires, Montevideo, and Colonia.

On his return to Great Britain, he was court-martialled and cashiered, mainly for surrendering Montevideo. Liniers was later named Viceroy of the Río de la Plata by the Spanish Crown.

Towards independence

Having to fight the British invasions by themselves, with little direct help from the Spanish Crown, and given that the Spanish King was captured by Napoleon, the idea of independence from Spain grew stronger.

Less than 3 years after the second invasion, the May Revolution took place in 1810, as a prelude to the Declaration of Independence of Argentina of 1816.