In assessing whether Spain, by 1572, had become an enemy rather than an ally to England, one must first define what exactly is meant by an ‘enemy’. Here, we will say that in order for the two nations to be defined as enemies in 1572, Spain and England must have been actively hostile toward each other. There are a host of factors that support this notion; their diplomatic relations had been increasingly awkward since England’s embassy had to be moved from Brussels to Madrid in 1559, thus distancing England from her interests in the Flemish market, ever since Philip II married Elizabeth of Guise in 1559, the spectre of a Catholic alliance became increasingly potent. And the seizure of 400,000 florins from Spanish ships sheltering in English ports in November 1568, and the subsequent trade embargo and retaliatory seizure of each other’s ships, seems to represent an actively hostile relationship. However, one must not predate the total deterioration of Anglo-Spanish relations; it was not until the treaty of Nonsuch in 1585, where Elizabeth endorsed English intervention in the Netherland, that war became inevitable between the two nations. Therefore, to the extent that there was an actively hostile foreign policy between England and Spain, it can be argued that the two nations were enemies 1572, a relationship signified by the signing of the Treaty of Blois in 1572. However, it must equally be stressed that war was not unavoidable. It is possible to identify three factors that led to Spain and England becoming ‘enemies’ by 1572; religious differences and the fear of a Catholic conspiracy, the importance of the Netherland to England’s economy and the desire for them to retain their autonomy, and the growing amity between England and France.
Garrett Mattingly famously asserted that it was religion, above all else, that determined the aggressive foreign policy between England and her continental neighbours; “Opposed ideologies would distort the lines of policy, cut across old allegiances, and multiply the hostilities between states by the implacable hatreds of conflict over absolute, transcendental ideas”. Certainly, the deterioration of Anglo-Spanish relations, which were at least on a ‘high politics’ level, very good, since the end of Mary’s reign, can be partly attributed to religious differences. Whilst the importance of religion in instigating war between the two countries has been undermined by recent studies, it was nevertheless instrumental in creating aggressive attitudes between England and Spain. It was not so much the intrinsic differences between Catholicism and Protestantism that fostered these attitudes; rather, it was the deep-seated, albeit slightly exaggerated, fear of a Catholic conspiracy. Certainly, it can be argued that Philip’s efforts to prevent Elizabeth’s excommunication for ten years after the passing of the Act of Supremacy in 1559 suggests that religious differences could be set aside in favour of a pragmatic alliance. However, one cannot take this to mean that religion was not a divisive factor in determining foreign policy. Rather, Philip II only tolerated England’s Protestantism to the extent that it did not manifest itself in an aggressive protestant foreign policy and he could not, due to financial problems and the menace of the Ottoman’s looming over him in the coming years, afford to launch an invasion. Furthermore, it was imperative for Philip to do maintain a relationship because of the terrifying prospect of Mary Stuart ascending the English throne and the consequent creation of a powerful French bloc extending through England and Scotland. The potential for Religious differences to foster hostilities between nations is very much apparent by the number of allusions to a Catholic conspiracy in the correspondence between councillors. Indeed, Cecil, who is traditionally purported to be a moderate protestant, exhibited fears of a Catholic alliance as he wrote that “Cardinal Lorraine”, the leader of the Catholic Guise faction in France, who was “conceived in a congregation of anti-Christ’s soldiers,” can never be thought to be “good by us”, because it is their [England’s] duty to “promote Christ’s kingdom and pull down the anti-Christ”. The Treaty of Hampton court of 1562 with the French Huguenots signified Elizabeth’s desire to maintain religious divisions in France, and to regain Calais, thus limiting the possibility of a Catholic alliance, supports this notion. It is not hard therefore, to imagine how the issue of religious differences roused suspicion between nations. Philip’s marriage to Elizabeth of Valois in 1559 certainly contributed to the growing fear of a Catholic alliance. These fears were exacerbated after a meeting between Catherine de’Medici and the Duke of Alva in Bayonne in 1565, where it was believed by many that plans were hatched to exterminate the protestant religion. Indeed, this fear seemed to materialise when, in 1568, the Duke of Alva was summoned to the Netherlands, along with an army swelling to 30,000 men, to crush the heresy following the iconoclastic fury of 1567. Sir Henry Norris wrote that if Alba was successful in suppressing the rebellion, “he will forthwith invade England”. Whilst Norris was a prominent hard-line protestant, these sentiments were shared by many other councillors. Furthermore, these fears were not unfounded; the Ridolfi plot of 1571 to assassinate and overthrow Elizabeth I using 10,000 of the Duke of Alba’s soldiers from the Netherlands, and which rose out of Elizabeth’s excommunication in 1570, seems ample justification such sentiments. Therefore, it will be stressed again that it was the fear of a Catholic alliance that drove hostilities between England and Spain to a point of enmity and, alternatively, active hostility, by 1572.
Let us now address the issue of the Netherlands and the resultant hostilities that aroused out of England’s desire to maintain its traditional semi-independence. The disastrous English occupation of Le Havre in 1562 had put Elizabeth off sending an expeditionary force to the aid of the Dutch rebels after the serious set-backs of 1568, where two rebel leaders, Horne and Egmont, were executed. However, Elizabeth did employ a policy of ‘harassment’, which included Sir Francis Drake’s raids on Spanish shipping in the New World. This would culminate in the seizure of 400,000 florins, intended to pay for Alba’s troops, from Spanish ships sheltering in the ports of Devon and Cornwall. The resultant lack of funds for Alva to pay his 30,000 soldiers and the threat of mutiny that corresponds would seriously hurt the Spanish efforts to suppress the revolt. Anglo-Spanish relations were severely tested in this episode; Philip was outraged and the Spanish ambassador to England, De Spes, advised him to retaliate by seizing English shipping and property in the Netherlands and Spain. Soon, a full trade embargo was implemented between the two nations. The fact that the embargo hurt Spain more than England, it was estimated that it was £20,000 pounds more costly for Spain, and that Spain’s treasury was, as Philip pointed out in his opening address, “exhausted”, intensified hostilities even further. It has been argued that Elizabeth’s decision to expel the sea beggars from English ports represents a desire to regain Philip’s favour after the failure of the Ridolfi plot and the expelling of De Spes from England with “even more indignity than Philip had used in the expulsion of Dr. Man” in 1568. However, whatever her intentions, it was seen by Philip as an actively hostile move, one that entailed in one of the most important victories of the Spanish revolt; the capture of Brielle in 1572. We may even trace a slight deterioration of relations between England and her Burgundian allies as far back as Mary’s reign and the introduction of higher duty taxes. However, this was not a politically motivated policy and did not result in any sort of the hostilities that ensued between 1567 and 1572. All this was coupled with a growing amity between England and France, which would culminate with The Treaty of Blois in 1572, thus establishing France as an ally against Spain. The fact that this treaty overcame long-held assumptions in English foreign policy, that France was the natural enemy, is indicative of strong hostility toward Spain. It may be argued that the St. Bartholomew’s Day massacre undermined these developments. However, Elizabeth did not exhibit much sympathy for the rebels.
Therefore, we will conclude that, as a result of religious differences and the exaggerated ‘bogey’ of a Catholic conspiracy, and Elizabeth’s desire to maintain the semi-autonomy of the Netherlands, Anglo-Spanish relations had deteriorated to the point of enmity by 1572. Whilst it can be argued that Anglo-Spanish relations during Mary’s reign were already very weak, especially due to the xenophobic sentiments behind Wyatt’s rebellion, they were nevertheless considerably stronger on a diplomatic and high political level. It is also important to reiterate that, whilst Anglo-Spanish relations were highly distressed, war was at no point inevitable; a point affirmed by the subsequent détente in relations between 1573 and 1576.

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[ 1 ]. Malcom R. Thorp, Catholic Conspiracy in Early Elizabethan Foreign Policy, p.433
[ 2 ]. Hume, Spain: Its Greatness and Decay (1479-1788) p.156