Águila, Don Juan del (c.1541?–1603?), Spanish general, was born in Barracco in the province of Avila, Spain. He joined the army, serving in Flanders, in the Mediterranean fighting the Turks, and then in Flanders once more, rising to become a commander of a regiment. Having completed twenty-four years of continuous military service, he returned to Spain for a time before being appointed commander of the 4,000–5,000 strong Spanish force sent to Brittany in 1590. Ostensibly dispatched to assist the Catholic League forces in France's religious civil war, his army was widely supported locally and quickly swept a rival English expeditionary force out of the province. However, local backing for Águila's forces evaporated as it became apparent that Spain intended holding Brittany indefinitely as a base from which to intervene in France or England. Inadequate support from Spain, quarrels with his own officers, and the increased strength of the French and English royal armies further undermined his military position. He lost a number of forts and towns during 1594, but managed to hold on in difficult circumstances for another three years. However, in summer 1597 his men mutinied, imprisoning him and his officers because of poor pay and harsh discipline. The Spanish force withdrew from Brittany in 1598 as part of the peace with France. In May 1600 he was imprisoned on charges of corruptly managing the royal finances placed in his hands during his time in Brittany. He was released in 1601 on condition that he lead an expedition to Ireland in support of the rebel forces there.
Initially, the Spanish government agreed with Águila that he should land at Donegal in order to link up with the armies of the main rebel leaders Red Hugh O'Donnell (qv) and Hugh O'Neill (qv), earl of Tyrone. However, O'Neill's agent in Spain, Mateo de Oviedo (qv), archbishop of Dublin, succeeded in persuading the council of war to order a landing in Munster, much to Águila's discontent. His misgivings increased when his government could raise only 4,400 men instead of the promised 6,000. Amid much bickering with his naval commander Brochero, his fleet set sail from Lisbon on 24 August (OS). While at sea, he held a council of war to determine his destination, his superiors having given him a choice between Cork and Kinsale. Oviedo argued forcefully in favour of landing at Cork, a bigger and more defensible town, but Águila believed it would prove too difficult to capture and insisted on Kinsale. The fleet was struck by a storm just as it approached the Irish coast on 17 September, driving away a number of ships. Águila eventually put in to Kinsale on 23 September, occupying the town after the royal garrison there fled. However, four ships – carrying about 650 men and most of his munitions and match – were blown back to Spain.
His pessimism deepened considerably in the days after his landing, as it became apparent that the Spanish had been misled by faulty intelligence. When the invasion had been proposed in 1600 much of Munster had been in rebellion and Florence MacCarthy Reagh (qv), a powerful Gaelic lord based in west Cork, had promised to assist the Spanish. Indeed, Kinsale's closeness to MacCarthy Reagh's territory had probably been its main attraction for Águila. However, in the intervening period, the rebellion had been largely subdued, MacCarthy Reagh arrested, and Spanish sympathisers cowed. As a result and contrary to expectation, the Spanish received virtually no local support after they landed. Deprived of guides to lead his army through an unfamiliar territory and unwilling to put to sea again for fear of further storms, he resolved to fortify Kinsale as best he could and await relief from the rebels in Ulster. However, its walls were thin, the surrounding hills dominated the town, and he lacked sufficient material to fortify properly either Kinsale or the outlying forts at Castle Park and Rincorran. Moreover, the loss of the ships carrying his munitions rendered much of his artillery unusable.
The adverse consequences of bad intelligence and bad luck were compounded by bad planning. First, the council of war had ordered the fleet to return to Spain as soon as it deposited the soldiers in Ireland. Águila had not objected to this, presumably because he assumed he would be able to move into the Irish interior, but now that he faced being besieged he urgently needed to keep his sea lines open. He could have countermanded the council's instructions, but permitted the ships to depart. Secondly, the government had assumed that he could buy horses from the local Irish to use as his cavalry, but Irish horses were markedly inferior to those in the rest of Europe and totally unsuited for battle. Lacking cavalry, naval and local support; a thousand miles away from his source of supply; and separated by the length of the country from his allies, his strategic position was disastrously weak.
In late October English forces under the command of the lord deputy of Ireland, Charles Blount (qv), Lord Mountjoy, camped in the vicinity of Kinsale. Mountjoy eventually mustered over 12,000 men and made good progress in besieging Kinsale during November. The Spanish were driven out of their trenches near the town, and the forts of Castle Park and Rincorran fell to the English, who were also able to begin an artillery bombardment of the town both by sea and by land. Meanwhile both Oviedo and many of Águila's captains became increasingly critical of their commander's passivity as the noose closed around them. In fact, his caution was vindicated by the irritation of the English commanders at his failure to engage them, as they hoped to wear down the Spanish in this way. Mountjoy and his officers were not particularly skilled at siegecraft and did not relish the prospect of storming a town defended by Spanish soldiers, then regarded as the best in Europe. Instead, they hoped to starve and bombard them into submission.
This strategy backfired: the Spanish found good cover in Kinsale and very few of them were killed by artillery fire. Moreover, although Águila's men suffered privations, it was the English, who were out in the open, who suffered dramatic casualties from exposure. Up to 6,000 of them are said to have died. In desperation, Mountjoy moved his army closer to the town in December in preparation for a direct attack. After repulsing a preliminary English assault on 10 December, Águila sallied out in large numbers for the first time two days later. His men destroyed two artillery platforms, forcing Mountjoy to call off his planned assault on the town. Elsewhere, the Hispano–Irish position continued to improve as the detachment of 650 men that had been forced to return to Spain landed in west Munster in December, while rebel forces from Ulster numbering about 6–7,000 approached Kinsale. Aware that the Irish had little experience of fighting on open ground, Águila ordered the commander of the west Munster detachment, Lopez de Soto, to send virtually all his men to assist the rebels. However, de Soto sent only 130 Spanish soldiers.
Nonetheless, the arrival of the rebel forces under O'Neill outside Kinsale in December threatened Mountjoy's gravely weakened forces, who were cut off on land by the rebels and at sea by adverse winds. Águila instructed O'Neill to establish his army atop a hill near Kinsale where the Spanish could see him. They would then link up with the Irish by breaking through the English trenches. This plan did not take into account the reluctance of the Irish to expose themselves to attack from the English. O'Neill harboured grave misgivings over his men's reliability in such a scenario but Águila eventually badgered him into agreeing.
Shortly after daybreak on 24 December 1601, the rebels had reached the agreed meeting point, but O'Neill almost immediately ordered a retreat. The Irish were pursued by a relatively small detachment from the main English army, were cut off by the English cavalry, fell into panic, and were routed. De Soto's failure to send more Spanish reinforcements to the Irish, which was not Águila's fault, proved crucial as the presence of more Spanish soldiers would have stiffened Irish resolve. In Kinsale the Spanish could hear the battle developing, but once O'Neill retreated from Águila's line of vision, there was little Águila could do to help his Irish allies, and only after the battle was over did he send his men out. There remains the suspicion that Águila did as little as possible to help his Irish allies, and was eager to heap the blame on them for the debacle.
At first, he continued his aggressive defence of the town, ordering successful sallies on 26–7 December, which destroyed five English artillery pieces. However, once O'Neill announced that he was retreating from Munster, Águila decided that the situation was hopeless and began surrender talks with Mountjoy, which were concluded after only two days on 2 January 1602. This was despite the fact that the English army remained exhausted by its exertions over the winter and was running low on supplies. The Spanish were permitted to leave Kinsale and return to Spain with all their equipment, supplies, and money. Controversially, Águila also agreed to order the surrender of three ports in west Munster given by local Irish to the Spanish under de Soto. In order to justify both his rather precipitate surrender and the generosity of its terms, he cast the Irish as treacherous and unreliable allies while exaggerating the strength of the English. He became overly friendly with Mountjoy and particularly with Sir George Carew (qv), lord president of Munster, who hoped to use him to drive a wedge between the Irish and the Spanish. Águila was happy to oblige, being aware that the preservation of his reputation now depended on vilifying his allies.
He landed at Corunna on 21 March 1602 to face a storm of criticism from Irish agents in Spain and from many of his subordinates, including de Soto. He robustly defended himself and counselled the king against sending further aid to the Irish rebels. The council of war immediately authorised a full investigation of the Irish campaign. In July 1603, this inquiry vindicated Águila's conduct as commander in Ireland. He seems to have reflected and benefited from a general war-weariness in Spain and an eagerness among the king's chief ministers to make peace with England. Although a justifiable military rationale can be found for every decision he made in Ireland, his strategy as a whole was excessively cautious. In particular, he could have done more to encourage and to assist O'Neill's men on the day of the battle of Kinsale. His betrayal of the Irish in west Munster by ordering the surrender of the Spanish-held forts there was indefensible and came to be viewed as such by Spanish officials, who treated Munster refugees with conspicuous generosity in recompense. Águila went to Ireland under duress, and his conduct there was marked by a desire to extract both himself and the Spanish crown from what he believed was a wasteful sideshow. Following his vindication, he retired to his native Avila, where he died soon after and was buried at Barraco. He is known to have married and had children.