The Thirty Years’ War in Italy

Relief of Genoa by the Marquis of Santa Cruz by Antonio de Pereda. Museo del Prado.
map of Italy in 1631

At the dawn of the seventeenth century, Spain’s position in Italy appeared impregnable, but appearances can be deceiving. The Italian princes used their small armies for short campaigns, such as Pope Clement VIII-who sent an expeditionary force against the Muslims in Hungary in 1595 and in 1601-2-or the Duchy of Modena, which waged war against the smaller Republic of Lucca in 1613.

Venice was the only independently powerful state in Italy. The intrinsic desire to remain independent of all influences often placed it at odds with Spain and the papacy. Venice’s senate compelled the papacy to seek senatorial approval for papal edicts issued in the republic. If the Senate disagreed with papal policy, it rejected decrees. This religious autonomy further exacerbated the rift between Rome and the republic.

In 1605 the disagreements between Venice and Rome finally reached a critical stage. Spain pledged Rome all possible military support, but failed to back its pledge with tangible forces. They feared possible French intervention, and thus a stalemate ensued. The diplomatic situation in Italy was complex, and thus in 1613 a confused and peculiar war was fought. Venice had difficulties with Dalmatian pirates, protected by the Austrian Habsburgs. A Venetian fleet attacked the pirates in their ports, and soon a maritime war expanded to the Italian mainland where Venetian troops attacked an Austrian army in Friuli. They fought on the same battlefields were, exactly three centuries later, Italians and Austrians would clash during World War I, on Carso and around the city of Gorizia. The Habsburg garrison was commanded by count Albrecht von Wallenstein, future general of Habsburg forces in Germany during the Thirty Years’ War.

The war at sea was known as the Uscock War, after the name of the Dalmatian pirates. The war against Austria was called the War of Gradisca, after the city attacked by Venetian forces. In the course of these wars Spain mobilized its forces in Milan to assist their Austrian Habsburg cousins. At the moment an expanded Habsburg-Venetian war appeared imminent, Duke Charles Emmanuel I of Savoy demanded the Duchy of Mantua for his house or, at least, the Marquisat of Monferrat. Spanish opposition to Savoyard expansion in April 1613 generated a war between the Italian duchy and Spain. Although the weight of forces favored Spain, the Spanish army from Milan was defeated and the duke resisted further Spanish threats. Surviving for the moment, Charles Emmanuel actively pursued a Venetian alliance. He sent an ambassador to Venice. Although the Senate welcomed the opportunity, it decided that this Spanish distraction served them better than an active war between Venice and Spain. They decided not to declare war against Spain but covertly cooperate with Savoy without an official alliance. Venice subsidized the Savoyard army; Charles Emmanuel sent troops to the Venetian army and with his war occupied Spanish resources in Italy.

The Neapolitan-that is to say Spanish-fleet appeared in the southern Adriatic, but the Venetian fleet was more than adequate to meet the challenge. The war stalemated, and soon the French became active in the Alps. The threat of French intervention compelled Philip III, king of Spain, to end the war before his territories in Italy were fully threatened by a French-Savoyard-Venetian alliance. In 1617, Madrid, Vienna, Turin, and Venice came to terms. Despite the conclusion of this Italian war, it was soon eclipsed by the greater European conflict looming on the horizon, the Thirty Years’ War.


The European conflict known as the Thirty Years’ War originated in 1618 as a result of an internal conflict between the king of Bohemia, Ferdinand II-Holy Roman Emperor and head of the Austrian Habsburgs-and the Protestant lords in Bohemia. They threw Ferdinand’s envoy and his assistants out of the castle window in Prague-the Defenestration of Prague-and then requested military support from the Evangelical Union in the Holy Roman Empire. Bohemia, a kingdom of the Austrian Habsburg realm, was one of the seven electoral territories in the Holy Roman Empire. The defiant Bohemian lords looked to the German Protestant princes in their rebellion against Ferdinand II, and offered Frederick, elector of the Palatinate, the crown of Bohemia.

The Holy Roman Emperor of the German Nation was elected by prince electors. If the House of Habsburg lost the crown of Bohemia, it lost the electoral capability as well as the possibility of maintaining the imperial crown in its hands. At the onset of this struggle for Bohemia, the House of Habsburg moved quickly to deal with this crisis, although it found itself overwhelmed with additional rebellions in Austria, too. All of this provided an opportunity for Frederick, as the Protestant Evangelical Union had no standing army and no diplomatic support abroad. Venice gave diplomatic support, because an enemy of Austria was a friend of the republic. Sweden and Denmark did the same, but Venice was richer and closer to Austria and Bohemia than Denmark and Sweden, therefore its support was of major importance to Frederick.

The problem remained building an army. It is here that Charles Emmanuel of Savoy became a central player. In 1617 he raised in Germany and paid in advance for an army of five thousand professional soldiers under General Ernst von Mansfeld. Initially, he wanted to employ it against Spain in northern Italy. With the war in Italy interrupted and the Evangelical Union needing an army, he left his forces in Germany. The Union’s ambassadors agreed that in exchange for his army, they support his interest in the imperial crown. As a prince of the empire they could vote for him. Charles Emmanuel accepted the proposition and his army went to Prague. Frederick had now diplomatic support and an army. He refused any possible accommodation with the Habsburgs, and the Thirty Years’ War began. The Evangelical Union did not keep its word; nonetheless, both Savoy and Venice had successfully diverted the Habsburg menace from Italy.

The emperor, Ferdinand II, was strongly funded by the Catholic world. His Spanish cousin, Philip III, gave him 1 million florins una tantum, but this was a trifle compared to the funds raised in Italy. Pope Paul V pledged 20,000 florins per month for the duration of the conflict. Then he permitted the emperor to levy a war tax in Italy, which brought in 250,000 scudi per year. The twelve congregations of the Catholic Church sent a 100,000-scudi gift, and this meant that, after 1623, the pope gave the emperor more money than Spain did. Moreover, the duke of Tuscany gave financial support and maintained a cavalry regiment in Germany throughout the war.

Thousands of Italians took part in the war, many of whom served as highranking officers in the imperial army. Famed soldiers such as Collalto, Galasso, Piccolomini, and Raimondo Montecuccoli fought under imperial and Spanish colors. Italian troops formed a significant part of the army that defeated Frederick and the Evangelical army at White Mountain in 1618; 14,000 were later led by the duke of Feria from Italy to Bavaria, as well as 16,000 led by the Habsburg Archduke Ferdinand (later Ferdinand III), who fought and won at Nördlingen in 1634. The greater part of Habsburg forces and finances were drawn from Italy.

The Spanish Road and the Struggle for Its Control: 1619-1640

Soon after the war began, Spain moved its troops north along the Spanish Road. It was impossible to prevent their movement in Italy, but it was possible to cut the Spanish Road in Switzerland, in the Valtelline. The Grisons were the masters of that Catholic and Italian-speaking valley, and they were Protestant. The advent of the Thirty Years’ War in Bohemia therefore affected Switzerland, too. A long and complicated war, the First Valtelline War began in 1620, when the local Catholics massacred all the Protestants living in the valley and, supported by the Spaniards, destroyed Protestant Swiss reinforcements coming from the north. The French, directed by Cardinal Richelieu, tried to cut the Spanish Road but repeatedly failed. Richelieu’s objective was to weaken the Habsburgs in Italy and Germany by supporting the local autonomies against Spain and Austria. He anticipated that this would compel Madrid and Vienna to use their military resources and their capital in Switzerland and Italy, to keep the Spanish Road opened, reducing their forces in Germany.

This policy of distracting the Habsburgs from their dynastic ambitions was drafted by King Henry IV and, after his assassination, it was continued and successfully exploited by his son’s minister Cardinal de Richelieu. From the early days of seventeenth century, the primary objective of French foreign policy was to supplant Habsburg power in Italy and Germany; failing that, to keep the Habsburgs weak in both regions. When in 1623 the major French effort to cut the Spanish Road in the Valtelline failed, France approached Savoy for an alliance. Richelieu’s intention was to conquer Genoa in order to cut the Spanish Road at its landing point in Liguria. In 1625, Charles Emmanuel of Savoy led a victorious campaign against Genoa, but as he anticipated consolidating his hold on the republic, French disorganization and Spanish intervention stopped him. Piedmontese troops were forced to leave Liguria and Spanish troops invaded Piedmont, thereby securing the the Spanish Road. In 1626 the Spanish army surrounded the key Piedmontese city of Verrua. The siege was long, terribly hard, and expensive. The Spaniards failed to take the city and decided to negotiate an end to the war. In any case, France failed again to cut the Spanish Road, and soon Spanish troops continued their march to Germany to support Catholic and Habsburg causes. The Protestants were defeated in Bohemia and in western and central Germany. Imperial troops defeated a Danish army under Christian IV and reached the borders of Jutland when the death of the duke of Mantua altered the course of the conflict.

Mantua was small, rich, and possessed major strategic importance in northern Italy. If the Spanish Road was cut, imperial troops could move from Germany to Italy only along a second, less protected, and less comfortable route. Venice owned the land in northern Italy from Switzerland to Adriatic coast, between Austrian and Spanish territories. Imperial troops could pass through the mountains separating the Trentino from Lombardy, then reach Lake Garda and sail down the Mincio river. Although the route passed through Venetian territory, the Venetians would allow them to sail down the river under condition of not landing on Venetian territory. Mantua was the terminal at the end of the journey. The master of the city controlled the only other imperial route through Italy.

In 1628, when duke Vincenzo Gonzaga died, his closest heir was the duke of Gonzaga-Nevers, descended from a branch of the family established in France. When the Spaniards realized that a French noble was the legal heir of Mantua and master of their second most important strategic city, they immediately threw their support behind the second Gonzaga branch, that of the former dukes of Ferrara. Venice and Paris declared their armies prepared to back Charles of GonzagaNevers. Ferdinand II then ordered his troops to Italy. The return of the imperial armies from Germany to Italy was a long-standing nightmare of the Church. Pope Urban VIII concentrated an army on his northern border, the bank of the Po river in front of Mantua, to prevent the introduction of imperial troops any farther south.

Cardinal de Richelieu saw Mantua as a new opportunity. A French-born duke in Mantua could cut the Habsburg’s strategic nerve. Mantua was far from the French frontier, and Richelieu’s army needed a secure passage through the Alps and a supply base in northern Italy. Lombardy was Spanish, but Mantua owned Monferrat, which was in Piedmont. If France could obtain free passage across the Alps with permission of Savoy, it could establish a horizontal strategic line running from the Alps through Casale-the capital of Monferrat-to Mantua, cutting both the Spanish Road, very close to Casale, and the Mantua route. The objective was so vital to French grand strategy that Richelieu personally led the French army into the Piedmont.

Charles Emmanuel I of Savoy was allied to Spain at this time, having been betrayed by the Evangelical Union and courted by Madrid. Richelieu tried to bargain, but the duke was clever. He negotiated with the cardinal while assembling his army. At the same time the new duke of Mantua raised an army; and both Venetian and imperial troops marched to Mantua. Gradually, more than 100,000 men from Savoy, Venice, Spain, the Papal States, Mantua, France, Naples, and the empire concentrated on the Padana Plain. It was the biggest concentration of troops ever seen during the Thirty Years’ War; and it occurred in Italy instead of in Germany.

In 1629, after the Danish phase of the Thirty Years’ War and prior to Swedish intervention, the turning point was reached in Italy. As C. V. Wedgwood remarked: “Insignificant in itself, the Mantuan crisis was the turning point of the Thirty Years’ War, for it precipitated the final division of the Catholic Church against itself, alienated the pope from the Habsburg dynasty, and made morally possible the calling of Protestant allies by Catholic powers to redress the balance.” Habsburg generals Ambrogio Spinola and Rambaldo di Collalto-both Italians- coordinated their efforts and, on July 18, 1630, Mantua fell and was pillaged by the imperials. Richelieu had captured Pinerolo, at the foot of the Piedmontese Alps, by this time, and the French and Mantuan garrison of Casale successfully kept the Spanish at bay. When this short and bloody war ended in 1630, the Treaty of Regensburg recognized the French presence in Italy and their possession of a passage across the Alps. The Spanish Road could now be cut from Casale; and the city-fortress could be supported by the French garrison at Pinerolo; and Pinerolo could be supplied from France thanks to the passage across the Alps. Richelieu had achieved a remarkable strategic success.

All was quiet on the Italian front for the following five years. Germany became the major operational theater once more; and Spain focused its attention and troops there. Long columns of soldiers under Spanish colors marched along the Spanish Road from Italy to Germany to fight and die on Dutch and German battlefields. The Spanish raised an enormous amount of money in Italy.

Their troops sailed from Italy to South America after 1624, when the Dutch attacked Brazil. Spain absorbed Portugal and its colonies until the 1640s, and found them susceptible to Dutch raids after 1621, when the twelve-year truce ended. The first Italian troops reached Saõ Joaõ da Bahia in 1625 and fought successfully against the Dutch. In 1635 the Neapolitan nobleman Giovan Vincenzo Sanfelice was appointed supreme commander of the Spanish troops in Brazil, and in 1638 he defeated Dutch troops attacking Bahia under John Maurice of Nassau.

The entire conflict in Europe changed in 1635 when France entered the war, backing the Protestants. Richelieu opened the Italian front with an alliance between France, Savoy, Mantua and Parma against Spain. Then a French army reentered the Valtelline to cut the Spanish Road. Spanish troops from Milan ejected the French; and Richelieu moved his army to Piedmont, while the duke of Modena joined Spain. After two years, a new peace was signed over the Valtelline, but the war continued in Piedmont until 1640. Piedmont, however, was racked by civil war between the duchess-sister of Louis XIII of France and mother of the young Duke Charles Emmanuel II-and princes Maurice and Thomas of Savoy who, as the brothers of the late Duke Victor Amadeus I, wanted the regency until their nephew could receive the crown.

France supported Duchess Christine and Spain backed the princes. After a three-year war, France and the duchess prevailed. The French retained their positions in Piedmont and menaced the Spanish Road once again. Richelieu followed up this change of fortune with another indirect attempt to weaken Spanish control of Italy. A local war exploded in central Italy in 1640. The so-called Castro War, after the name of a little fief some sixty miles north of Rome, involved a coalition composed of Venice, Parma, Modena and Tuscany in a conflict against the pope. The clash had no impact on the war in Germany, but it diverted men and resources and forced Spain to retain troops in Italy. All the Italian states involved recalled their best men serving abroad. Among them was Raimondo Montecuccoli, appointed commander of the Modenese troops who conducted an impressive campaign against papal troops around Bologna.

This bloody war, with casualties on both sides exceeding 14,000 men in twenty-three months, ended in 1644, with no significant changes to the political situation in Italy.

Cardinal Mazarin, successor to Richelieu, decided to act directly against Spain. In 1646 a 10,000-man French expeditionary force landed in the Presidii to cut the maritime portion of the Spanish Road. Operations went on slowly, but in 1647, Naples, the financial and military center of Spanish power in Italy revolted against the Spanish viceroy. The root cause of the revolt was the excessive taxation by the Spanish to sustain their war in the Netherlands and Germany. When in July 1647 a new tax was levied on fruits and vegetables, the people revolted. No less than 115,000 people took arms against the viceroy, who escaped to Naples’ main castle. The Spanish garrison was unable to stop the riots, and in October the revolution expanded throughout southern Italy. Madrid dispatched all available galleys and troops to Naples. No less than 40 galleys and vessels and more than 3,000 cannons, including those in the fortresses, were employed. The expedition failed; and Naples fell to the rebellion. The Royal Neapolitan Republic-as the revolutionary government named itself-requested assistance from France. A French fleet arrived before the city on December 24, 1647, and fought a naval battle against the Spanish while the French duke of Guiche was proclaimed chief of the Royal Neapolitan Republic.

Spain increased troops and ships in the area. At the same time the Spanish promised money and honors to all who would help them, as well as a general pardon to the city and its inhabitants. In spring 1648 the money succeeded where the weapons had failed; and the duke of Guiche was captured by Spanish forces.

The Peace of Westphalia ended the war in Europe, but the Thirty Years’ War left unresolved problems and new animosities. France attained its strategic goals. Germany and Italy remained divided into small weak states. According to the treaty, France could intervene in German affairs to defend Protestant rights. German princes could seek French protection when in conflict with the emperor. France used this power for diplomatic and military purposes into the eighteenth century.

The situation in Italy differed because the Treaties of Westphalia did not address the situation in the peninsula. France, however, retained control of the Alpine passes and the fortress of Pinerolo. This gave them a direct control over the Piedmont and the effective means to cut the Spanish Road and the Spanish logistical system.