The Siege of Montevideo, 1807

Spanish Defense Section 1:

On 30 October 1806 a new 2,180 man British force under Lt:. Col. Backhouse captured the open port of Maldonado from it's few local militia, but then had to vegetate for two months observed by 400 Spanish militia cavalry, who made foraging increasingly difficult. In January 1807 a belated British relief expedition under Brigadier Auchmuty (including the force originally destined for Chile) rescued them from an increasingly precarious situation, and the two forces, totalling 6,300 men, landed nine miles from Montevideo on 16 January. The Viceroy sent a Campo Volante to oppose them.

CAMPO VOLANTE, MONTEVIDEO, 19 JANUARY 1807
R	Inf. Regt. of Buenos Aires	260
R	Drag. Regt. of Buenos Aires	170
?	Militia Cav.	1,700
?	Militia Infantry	200
.	Artillery - 2 x 8 pdr, 2 x 6" Howitzers, + 9 other cannon

Heavily outnumbered, the Campo Volante was easily driven off. Most of the militia cavalry were dispersed and only the regulars retreated in good order into Montevideo. The following day virtually the entire garrison was thrown into a surprise sortie, leaving only some 100 regular and 400 militia artillery on the walls to man some of the fortress's 150 cannons, 6 Howitzers and 11 mortars.

MONTEVIDEO SORTIE, 20 JANUARY 1807
R	Regt. de Inf. de B.A.	270
R	Regt. de Drag. de B.A.	260
MD	Bat. de Vol. de Montevideo	650
MD	Militia Cavalry	422
P	Volunteer Hussars	300
P	Cuerpo de Miņones	200
P	Cazadores	60
.	2 Coys. Sailors and Marines	200
Total		2,362

The British lost about 25 dead and 100 wounded, but the Spanish were bloodily repulsed with the loss of a third of their strength as casualties. Much of the remaining militia cavalry were dispersed into the interior, where they could only slowly be reassembled by the rather ineffectual Viceroy as a campo volante to harass the British rear. This was probably the only occasion when regular Spanish colonial units engaged the British in conventional battle. The steadiness of the few colonial regulars in covering the withdrawal back into the city against overwhelming enemy numbers, after heavy casualties and the collapse of their militia, was remarked on by the British at the time, and indicates that the determination of Spanish colonial forces should not be dismissed out of hand, despite their manifold weaknesses.

As a result of this action, Montevideo's garrison was reduced to only 1,400 men, amongst whom there were only 200 regulars. Yet, 1,200 men were required to fully man all the fortress artillery alone! Buenos Aires managed to slip a further 108 infantry, 78 dragoon and 325 Blandengues regulars into Montevideo during the siege, but almost all were lost when the British stormed the city on 3 February. British losses in the assault were 120 dead and 277 wounded. Due to weak leadership by the Viceroy, the Campo Volante proved completely ineffective in harassing the British rear.

The loss of Montevideo was effectively the end of the Spanish imperial defence system in La Plata. Its main fortification had fallen, along with almost all the small local naval squadron, and there were virtually no regular troops left in the colony. It was mostly newly raised local units that were to force the British under Whitelocke into a humiliating surrender at Buenos Aires on 7 July 1807; an event that therefore falls outside any study of the conventional imperial defence system.

The Proposed Invasion of Chile

Chile was an agricultural colony supplying Peru and not especially valuable of itself. Therefore the British were not interested in its occupation as such, to them it only represented a potential base for more lucrative expeditions up the Pacific coast to Peru. When Admiral Anson had arrived off Chile in 1741, he was entering waters little known to British sailors. Half his force had been driven back or wrecked off Cape Horn, his men suffered dreadfully from scurvy and his ships badly needed careening. By 1806 many other British sailors had passed the Horn successfully, the waters were more familiar, scurvy had been held at bay by lime juice, and the copper-bottoming of warships made careening necessary less often.

Furthermore, even the Spanish, little respected by the Royal Navy for their seamanship, had successfully sent considerable squadrons to Callao via the Horn in the 1770s and 1780s. The naval preconditions for a successful landing were therefore in place. The British expedition assembled in 1806 to attack Chile under Craufurd contained 4,800 infantry and a regiment of light dragoons. In the event it was diverted to Montevideo. By the time it disembarked there, some of its troops had been nine months aboard ship. Yet they still landed fit, a clear indication that health need not have inhibited an invasion of Chile.

The best prospective British target was the island of Chiloe. Its population consisted of a manageable 15,000 Criollos and Mestizos, and 12,000 Indians. There was apparently no regular garrison at this time, although 480 militia cavalry and 1,699 militia infantry could be raised. However, they were greatly inferior in both numbers and quality to the prospective British invasion force. The island had five artillery batteries fortified on their seaward side, but all were undefended on their landward side. Thus Chiloe was very vulnerable to any British attack that might reach it.

Furthermore, as an island, it could then easily be defended against the very weak Spanish fleet in the Pacific by even a small Royal Navy squadron, as the embryonic Chilean Navy proved a decade later. Finally, Chiloe had a temperate climate, which promised to reduce disease attrition to low levels, was self-sustaining in food, and was a recognised source of lumber for ship construction and repair. In short, it offered a secure and very promising base for exploitation further up the Pacific coast. If the British wished to go on to attack wealthy Peru, the possession of Chiloe made a landing on the Chilean mainland unnecessary. All that was needed was to blockade Valparaiso so that vital Chilean food exports could not reach Callao and Lima.

Chile's mainland defences were larger, but had their own weaknesses. (The following figures relate to the regulations of 1778, which seem to have still been in force in 1805). The regular army consisted of two battalions of the Regimiento de lnfanteria de la Frontera (sixteen companies), the Regimiento de Dragones de la Frontera (eight companies), and two companies of artillery, totalling 1,250 men. As in La Plata, these were widely dispersed. 80% of regulars were concentrated on the ports of Valdivia and Concepcion and the nearby Indian frontier, all in the south.

Further north, the main defence was the more numerous militia. This primarily consisted of Milicias Disciplinadas and Milicias Urbanas, which suffered the same flaws as those of La Plata. There were also intermediate Milicias Regladas (Regulated Militias), which had the same obligations as the Milicias Disciplinadas, but did not receive such regular training. They were almost as untutored as the Milicias Urbanas. The Milicias Disciplinadas consisted of thirteen mounted regiments (7,800 men), two mounted squadrons (300 men), and three infantry battalions (2,098 men). Only two companies of regulars were stationed at the unfortified inland capital of Santiago:

District Santiago
Type	Units	Men	Title / Race
R	Infantry Company	53	from Frontera Regt.
R	Dragoon Company	53	de la Reina
MD	Cavalry Regiment	600	del Principe
MD	Cavalry Regiment	600	de la Princesa
MD	Infantry Regiment	840	del Rey
MU	Infantry Battalion	350	de Comercio
MU	Five Infantry Companies	250	Pardos
MU	Two Cavalry Squadrons	300	de Borbon

Although there were thousands more Milicias Disciplinadas in the area around Santiago and the port of Valparaiso, through which ran the capital's outside communications, the resident garrison of the port itself was conspicuously weak;

District Valparaiso
Type	Units	Men	Title / Race
R	Dragoon Company	53	from Frontera Regt.
R	Artillery Company	53	.
MD	Infantry Battalion	308	del Infante de Asturias
MR	Artillery Company	?	.
MD	Cavalry Squadron	150	.
MU	Infantry Company	?	de Comercio

There is no reason to believe that the regulars and militias of Chile had any more prospect of successfully defeating the British in the open field than had those of La Plata. Nor did Chile possess a fortress as strong as Montevideo, or a city as populous and complex as Buenos Aires, so there is every possibility that the British could have established themselves ashore in a port. There was also little immediate prospect of support from Peru, which had barely enough regular troops to garrison Callao, too weak a fleet to safely transport them by sea, and ill-trained Milicias Disciplinadas notoriously unwilling to leave their home areas.

If establishing a base ashore in Chile was likely to prove quite possible, its regular maintenance via Cape Horn was likely to be more difficult. Consideration was therefore given to establishing land communications with Buenos Aires. Creating a string of outposts between the two colonies was not a completely "wild" idea. The Spanish had already built one. It is likely that the British knew this and probably intended to simply replace the existing Blandengues de Buenos Aires and Dragones de la Frontera garrisons with pickets of light dragoons. As frontier forces largely schooled in irregular warfare, the Spanish garrisons could probably have been driven out of their posts by regular troops.

However, the only chance the British would have had of maintaining their own tiny interior garrisons and tenuous communications to Buenos Aires was if they could reach a peaceful accommodation with the local Criollos. This was precisely Craufurd's instruction, but unfortunately the confiscation of the Viceregal treasury during the Beresford's earlier raid on Buenos Aires had already confirmed the British reputation for plundering, and the subsequent capture of his entire force had damaged British military prestige and greatly boosted Criollo self confidence.

Thus Craufurd's chances of securing the passivity of the Chilean population were much reduced. In the face of any irregular guerrilla campaign by the Dragones, Blandengues and proto-gaucho militia, the British could only have withdrawn to the coast or allied themselves with local Indians. The Indians in both southern La Plata and southern Chile were still independent. Normally they tied down half the regular Spanish defence establishment in the former colony and four-fifths in the latter. However, there is no indication that the British had even considered such an alliance, and had they done so it would have instantly and irrevocably alienated all the Criollos.

It is worth repeating that, if they possessed Chiloe, there was no absolute necessity for the British to get involved in a campaign on the Chilean mainland at all.

Popular Revolt

What defeated the British at Buenos Aires was unexpected, Criollo led, popular resistance outside the traditional administrative and military structures of the Peninsular-dominated colonial establishment, which had been comprehensively defeated. The British had little reason to anticipate this. They had connived with leading Criollos across the Americas for generations to smuggle contraband in defiance of Peninsular prohibitions.

The open collaboration of the Criollo elite during the occupation of Havana in 1762-3 had delighted the British and badly shaken the Spanish government's confidence in the loyalty of its Criollo subjects. More recently the agitation of Francisco de Miranda had convinced many in Britain that the Criollos were anxious to throw off the Peninsular yoke with British help, and subsequent decades were to prove that he was not entirely fanciful, even though his attempt to seize Nueva Granada was decisively repulsed in 1806, when he conspicuously failed to induce a popular, Criollo-led uprising. Even at Buenos Aires the population was initially quiescent and there were numerous collaborators.

It is important to note that the lack of significant fortifications at Buenos Aires was unique for so important a Spanish colonial port, and that this quite possibly produced unique results. In particular, it provided the only environment in which ill-trained popular militia forces might hope to defeat British regulars, given that the British showed little inclination to expose themselves to guerrilla war in the interior.

Other Spanish colonial populations might have reacted equally strongly against the British, but few would have enjoyed the happy conjunction of circumstances which let the people of Buenos Aires inflict a major military defeat on them. The limited Spanish resources had gone into fortifying nearby Montevideo against the more imminent Portuguese threat from Brazil and this was a more typical colonial city. There the British found no insurmountable problems in taking the fortifications or controlling the population. The British surrendered Montevideo in exchange for the army lost at Buenos Aires, not because it was yet threatened from either within or without.

It is only with our retrospective knowledge of the imminence of the Spanish American Independence Wars that either the popular uprising in Buenos Aires or its success appears inevitable, even though neither probably was, and it is by no means necessarily the case that the populations of either Chile or Mexico would react in either the same way or as effectively, especially if they failed to throw up a leader of the calibre of Liniers.

What appears to have provoked the resistance at Buenos Aires was the blatant weakness of Beresford's initial force and the injury to local pride this caused. It is quite possible that a greater initial show of force might have stifled significant popular resistance. Even the final British assault on Buenos Aires under Whitelocke should have crushed it, if properly handled. Of all the combats in the Plate campaign of 1806-7, only the result of this last should surprise observers. All the others had predictable outcomes given the circumstances, numbers and experience of the contenders. Ultimately much, perhaps all, turned on the characters of the indefatigable Liniers and the inadequate Whitelocke.

Naval Obstacles

The problem facing the navy was not the ability to transport a large army over such great distances (except across the Pacific), nor was it likely to have to contend with significant seaborne opposition of the sort that had sealed the surrender at Yorktown. The problem facing the navy was to continuously maintain the army once ashore if the interior proved hostile. The dire straits to which Backhouse's 2,180 regulars were reduced by as few as 400 irregular Spanish colonial militia cavalry restricting their ability to forage between landing at Maldonado on 29 October 1806 and relief by Auchmuty on 5 January 1807, illustrates how vital regular maintenance from the sea might prove and how difficult it could be to sustain even small forces at such a distance. However, for a Royal Navy which had already supported operations as far flung as the Cape of Good Hope, the Dutch East Indies and the Philippines, this was not insurmountable, merely strenuous and expensive.

Conclusion

That the British could project sufficient naval and military power to overwhelm the regular defences of most of the targeted Spanish colonies and gain a lodgement ashore, as they did initially at Buenos Aires and later at Montevideo, is highly probable, although logistics problems made a significant Pacific invasion of Mexico unlikely. Once ashore, practical plans had been made to avoid the disease losses that had destroyed earlier expeditions, but the twin imponderables of British error and widespread popular resistance, both evident at Buenos Aires, obscure the likely end results of invasions of the Philippines, Mexico and Chile.

However, to assume that Wellesley in Mexico or Craufurd in an independent command in Chile would have proved as incompetent a Whitelocke at Buenos Aires flies in the face of their exceptional records in the Peninsular War. It is thus reasonable to assume that the invasions of Mexico and Chile were likely to be far better managed affairs than Buenos Aires,, and that comparable British error could not be relied upon.

The question of popular resistance is less easily dismissed. Certainly, if skilled British commanders had landed with overwhelming numbers of troops, a repeat of the (probably reversible) events at Buenos Aires might have been avoided in Chile and Mexico. However, for the British to have mastered more than a few major coastal centres in these colonies, and to have occupied anywhere in the interior for long against popular opposition, would probably have required major reinforcement and extended campaigns.

The strain of trans-Atlantic, continental-scale campaigning against popular resistance imposed on Britain in North America during the American War of Independence and France in Mexico during the 1860s are well recorded, and do not augur well for the long term prospects of the British in Spanish America in 1805-8 under similar circumstances. It is ironic that the British were actually defeated in the one colony where they had some long term prospect, although not intention, of colonising; La Plata.

It would therefore seem that, with the exception of the dubious invasion of Mexico from the Pacific, the various British invasion plans were neither as wild, nor as incredible, nor as fantastic as usually assumed, and none need necessarily have turned into a debacle on the scale of Buenos Aires. Indeed, neither should Buenos Aires. What stopped them was not their impracticability, but the fact that they were not given priority over equally far flung and generally successful operations in Africa and Asia. Even the initial invasion of La Plata was the result of local initiative by an expedition to the Cape of Good Hope, not government policy. However, the British invasion projects were definitely ambitious and not without considerable risk. Perhaps fortunately for both parties, the outbreak of the Peninsular War threw Britain and Spain into an unexpected alliance before they could lock horns and resolve these questions definitively.

Abbreviations Used

N.B. For the sake of simplicity, the following abbreviations are used on the orders of battle above:

R Regular,
DM Milicias Disciplinadas,
MR Milicias Regladas,
P Patriotas.
MU Milicias Urbanas

Glossary of Colonial Racial terms

The Spanish colonies had a hierarchical social system based on racial origin, which also affected their level of military obligations:

Peninsular: Spanish-born White.
Criollo: Colonially-born White.
Mestizo: Mixed Spanish/Indian descent.
Pardo or Mulatto: Mixed Black/Other descent.
Moreno: Black
Indio: Amerindian

There were numerous other classifications for different combinations of the above, but they were too complex to have practical application and tended to be submerged under the designations Mestizo, Pardo or Mulatto. Axworthy.

( Many thanks Mark for this interesting insight into these campaigns. T.D.H. )

Spanish Defense Section 1: