The Thirty Years’ War was fought between 1618 and 1648, principally on the territory of today’s Germany, and involved most of the major European powers.

Beginning as a religious conflict between Protestants and Catholics in the Holy Roman Empire, it gradually developed into a general war involving much of Europe, for reasons not necessarily related to religion.

The war marked the culmination of the France-Habsburg rivalry for pre-eminence in Europe, which led to further wars between France and the Habsburg powers.

The major impact of the Thirty Years’ War, in which mercenary armies were extensively used, was the devastation of entire regions scavenged bare by the foraging armies. Episodes of widespread famine and disease devastated the population of the German states and, to a lesser extent, the Low Countries and Italy, while bankrupting many of the powers involved.

The war may have lasted for 30 years, but the conflicts that triggered it continued unresolved for a much longer time. The war ended with the Treaty of Münster, a part of the wider Peace of Westphalia.

Over the course of the war, the population of the German states was reduced by about 30%;[4] in the territory of Brandenburg, the losses had amounted to half, while in some areas an estimated two-thirds of the population died. Germany’s male population was reduced by almost half. The population of the Czech lands declined by a third. The Swedish armies alone destroyed 2,000 castles, 18,000 villages and 1,500 towns in Germany, one-third of all German towns.

The Peace of Augsburg (1555), signed by Charles V, Holy Roman Emperor, confirmed the result of the 1526 Diet of Speyer and ended the violence between the Lutherans and the Catholics in Germany.

• German princes (numbering 225) could choose the religion (Lutheranism or Catholicism) of their realms according to their consciences (the principle of cuius regio, eius religio).
• Lutherans living in an ecclesiastical state (under the control of a bishop) could continue to practice their faith.
• Lutherans could keep the territory that they had captured from the Catholic Church since the Peace of Passau in 1552.
• The ecclesiastical leaders of the Catholic Church (bishops) that had converted to Lutheranism were required to give up their territories (the principle called reservatum ecclesiasticum).

Those occupying a state that had officially chosen either Protestantism or Catholicism could not practice a religion differing from that of the state.

Although the Peace of Augsburg created a temporary end to hostilities, it did not solve the underlying basis of the religious conflict.

In addition, Calvinism spread quickly throughout Germany in the years that followed. This added a third major faith to the region, but its position was not recognized in any way by the Augsburg terms, to which only Catholicism and Lutheranism were a party.

The rulers of the nations surrounding the German states also contributed to the outbreak of the Thirty Years’ War:

• Spain was interested in the German states because it held the territories of the Spanish Netherlands on the western border of the German states and states within Italy which connected by land through the Spanish Road.
• The Dutch revolted against the Spanish domination during the 1560s, leading to a protracted war of independence that led to a truce only in 1609.
• France was threatened by two surrounding Habsburg states (Spain and the Holy Roman Empire), and was eager to exert its power against the weaker German states
  • this dynastic concern overtook religious ones and led to Catholic France’s participation on the otherwise Protestant side of the war.
• Sweden and Denmark were interested in gaining control over northern German states bordering the Baltic Sea.
• The Holy Roman Empire was a fragmented collection of independent powers.
  • One of these, the Austrian House of Habsburg (including also Bohemia and Hungary), was a major European power, ruling over some eight million subjects.
  • The Empire also contained several regional powers, such as Bavaria, Electoral Saxony, the Margraviate of Brandenburg, the Palatinate, Hesse, the Archbishopric of Trier and Württemberg (containing from 500,000 to one million inhabitants).
  • A vast number of minor independent duchies, free cities, abbeys, bishoprics, and petty lords (whose authority sometimes extended to no more than a single village) rounded out the Empire.
  • Apart from Austria and perhaps Bavaria, none of those entities was capable of national-level politics;
    • alliances between family-related states were common,
    • due partly to the frequent practice of splitting a lord’s inheritance among the various sons.

Religious tensions remained strong throughout the second half of the 16th century.

The Peace of Augsburg began to unravel as some converted bishops refused to give up their bishoprics, and as certain Catholic rulers in Spain and Eastern Europe sought to restore the power of Catholicism in the region.

This was evident from the Cologne War (1583-88), a conflict initiated when the prince-archbishop of the city converted to Calvinism.

As he was an imperial elector, this could have produced a Protestant majority in the College that elected the Holy Roman Emperor – a position that had always been held by a Catholic.

In the Cologne War, Spanish troops expelled the prince-archbishop and replaced him with Ernst of Bavaria, a Roman Catholic. After this success, the Catholics regained pace, and the principle of cuius regio eius religio began to be exerted more strictly in Bavaria, Würzburg and other states. This forced Lutheran residents to choose between conversion or exile.

Lutherans also witnessed the defection of the lords of Palatinate (1560), Nassau (1578), Hesse-Kassel (1603) and Brandenburg (1613) to the new Calvinist faith.

Thus at the beginning of the 17th century the Rhine lands and those south to the Danube were largely Catholic, while Lutherans predominated in the north, and Calvinists dominated in certain other areas, such as west-central Germany, Switzerland and the Netherlands.

However, minorities of each creed existed almost everywhere. In some lordships and cities the number of Calvinists, Catholics, and Lutherans were approximately equal.

Much to the consternation of their Spanish ruling cousins, the Habsburg emperors who followed Charles V (especially Ferdinand I and Maximilian II, but also Rudolf II, and his successor Matthias) were supportive of their subjects’ religious choices. These rulers avoided religious wars within the empire by allowing the different Christian faiths to spread without coercion. This angered those who sought religious uniformity.[citation needed] Meanwhile, Sweden and Denmark, both Lutheran kingdoms, sought to assist the Protestant cause in the Empire, and also wanted to gain political and economic influence there as well.

Religious tensions broke into violence in the German free city of Donauwörth in 1606.

There, the Lutheran majority barred the Catholic residents of the Swabian town from holding a procession, which provoked a riot.

This prompted foreign intervention by Duke Maximilian of Bavaria (1573–1651) on behalf of the Catholics.

After the violence ceased, Calvinists in Germany (who remained a minority) felt the most threatened. They banded together and formed the League of Evangelical Union in 1608,

under the leadership of the Palatine elector Frederick IV (1583–1610), (whose son, Frederick V, married Elizabeth Stuart, the daughter of James I of England).

Incidentally, the Prince-Elector had control of the Rhenish Palatinate, a state along the Rhine that Spain sought to acquire.

The establishment of the League prompted the Catholics into banding together to form the Catholic League in 1609, under the leadership of the Duke Maximilian.

By 1617 it was apparent that Matthias, Holy Roman Emperor and King of Bohemia, would die without an heir, with his lands going to his nearest male relative, his cousin Ferdinand of Styria.

Ferdinand became King of Bohemia and Ferdinand II, Holy Roman Emperor in 1619 when Matthias died.

Ferdinand, having been educated by the Jesuits, was a staunch Catholic who wanted to impose religious uniformity on his lands. This made him highly unpopular in primarily Hussite Bohemia.

The rejection of Ferdinand, who had been elected Bohemian Crown Prince in 1617, triggered the Thirty Years’ War in 1618 when his representatives were defenestrated in Prague.

This defeat led to the dissolution of the League of Evangelical Union and the loss of Frederick V’s holdings.

• Frederick was outlawed from the Holy Roman Empire and his territories, the Rhenish Palatinate, were given to Catholic nobles.
• His title of elector of the Palatinate was given to his distant cousin Duke Maximilian of Bavaria.
• Frederick, now landless, made himself a prominent exile abroad and tried to curry support for his cause in Sweden, Netherlands and Denmark.

This was a serious blow to Protestant ambitions in the region.

As the rebellion collapsed, the widespread confiscations of property and suppression of the Bohemian nobility ensured that the country would return to the Catholic side after more than two centuries of Hussite and other religious dissent.

The Spanish, seeking to outflank the Dutch in preparation for renewal of the Eighty Years’ War, took Frederick’s lands, the Rhine Palatinate. The first phase of the war in eastern Germany ended 31 December 1621, when the Prince of Transylvania and the Emperor signed the Peace of Nikolsburg, which gave Transylvania a number of territories in Royal Hungary.

• In addition, the Spanish ambassador to Vienna, Don Iñigo Vélez de Oñate, persuaded Protestant Saxony to intervene against Bohemia in exchange for control over Lusatia.
• The Saxons invaded, and the Spanish army in the west prevented the Protestant Union’s forces from assisting.
• Onate conspired to transfer the electoral title from the Palatinate to the Duke of Bavaria in exchange for his support and that of the Catholic League.
• Under the command of General Tilly, the Catholic League’s army (which included René Descartes in its ranks) pacified Upper Austria, while the Emperor’s forces pacified Lower Austria.
• The two armies united and moved north into Bohemia. * Ferdinand II decisively defeated Frederick V at the Battle of White Mountain, near Prague, on 8 November 1620.
  • In addition to becoming Catholic, Bohemia would remain in Habsburg hands for nearly three hundred years.

Some historians regard the period from 1621–1625 as a distinct portion of the Thirty Years’ War, calling it the “Palatinate phase”.

With the catastrophic defeat of the Protestant army at White Mountain and the departure of the Prince of Transylvania, greater Bohemia was pacified.

However, the war in the Palatinate continued.

This phase of the war consisted of much smaller battles, mostly sieges conducted by the Spanish army.

Mannheim and Heidelberg fell in 1622, and Frankenthal was taken two years later, thus leaving the Palatinate in the hands of the Spanish.

Peace in the Empire was short-lived, however, as conflict resumed at the initiation of Denmark.

Danish involvement began when Christian IV of Denmark, a Lutheran who was also the Duke of Holstein, a duchy within the Holy Roman Empire, helped the Lutheran rulers of neighbouring Lower Saxony by leading an army against the Imperial forces.

Denmark had feared that its sovereignty as a Protestant nation was threatened by the recent Catholic successes.

• For instance, in 1621, Hamburg had been forced to accept Danish sovereignty and Christian’s second son was made bishop of Bremen.
• Christian IV had obtained for his kingdom a level of stability and wealth that was virtually unmatched elsewhere in Europe.
  • This stability and wealth was paid for by tolls on the Oresund and also by extensive war reparations from Sweden.
• Denmark’s cause was aided by France which, together with England, had agreed to help subsidize the war.
• Christian had himself appointed war leader of the Lower Saxon Circle and raised an army of 20,000 mercenaries and a national army 15,000 strong.

• Although their arrival did help to lift the siege of Bergen-op-Zoom, the Dutch could not provide permanent shelter for them.
• They were paid off and sent to occupy neighboring East Friesland.
• Mansfeld remained in Holland, but Christian wandered off to “assist” his kin in the Lower Saxon Circle, attracting the attentions of Tilly.
• With the news that Mansfeld would not be supporting him, Christian’s army began a steady retreat toward the safety of the Dutch border.
• On 6 August 1623, Tilly’s more disciplined army caught up with them 10 miles short of the Dutch border.
  • The battle that ensued was known as the Battle of Stadtlohn.
  • In this battle Tilly decisively defeated Christian, wiping out over four-fifths of his army, which had been some 15,000 strong.

After this catastrophe, Frederick V, already in exile in The Hague, and under growing pressure from his father-in-law James I to end his involvement in the war, was forced to abandon any hope of launching further campaigns.

The Protestant rebellion had been crushed.

To fight him, Ferdinand II employed the military help of Albrecht von Wallenstein, a Bohemian nobleman who had made himself rich from the confiscated estates of his countrymen.

Wallenstein pledged his army, which numbered between 30,000 and 100,000 soldiers, to Ferdinand II in return for the right to plunder the captured territories.

Christian, who knew nothing of Wallenstein’s forces when he invaded, was forced to retire before the combined forces of Wallenstein and Tilly.

• England was weak and internally divided,
• France was in the midst of a civil war,
• Sweden was at war with the Polish-Lithuanian Commonwealth,
• and neither Brandenburg nor Saxony were interested in changes to the tenuous peace in eastern Germany.

Wallenstein defeated Mansfeld’s army at the Battle of Dessau Bridge (1626) and General Tilly defeated the Danes at the Battle of Lutter (1626).

Mansfeld died some months later of illness, in Dalmatia.

Wallenstein’s army marched north, occupying Mecklenburg, Pomerania, and ultimately Jutland itself.

However, he was unable to take the Danish capital on the island of Zealand. Wallenstein lacked a fleet, and neither the Hanseatic ports nor the Poles would allow an Imperial fleet to be built on the Baltic coast.

He then laid siege to Stralsund, the only belligerent Baltic port with the facilities to build a large fleet.

However, the cost of continuing the war was exorbitant compared to what could possibly be gained from conquering the rest of Denmark, and so Wallenstein decided to make peace.

Negotiations were concluded with the Treaty of Lbeck in 1629, which stated that Christian IV could keep his control over Denmark if he would abandon his support for the Protestant German states.

Thus, in the following two years more land was subjugated by the Catholic powers.

At this point, the Catholic League persuaded Ferdinand II to take back the Lutheran holdings that were, according to the Peace of Augsburg, rightfully the possession of the Catholic Church.

Enumerated in the Edict of Restitution (1629), these possessions included two Archbishoprics, sixteen bishoprics, and hundreds of monasteries. The same year, Mansfeld and Gabriel Bethlen, the first officers of the Protestant cause, died.

Only the port of Stralsund continued to hold out against Wallenstein and the Emperor.

Swedish intervention

Some within Ferdinand II’s court did not trust Wallenstein, believing that he sought to join forces with the German Princes and thus gain influence over the Emperor.

Ferdinand II dismissed Wallenstein in 1630. He was to later recall him after the Swedes, led by King Gustaf II Adolf (Gustavus Adolphus), had invaded the Empire with success.

Gustavus Adolphus, like Christian IV before him, came:

• to aid the German Lutherans,
• to forestall Catholic aggression against their homeland,
• and to obtain economic influence in the German states around the Baltic Sea.
• In addition, Gustavus was concerned about the growing power of the Holy Roman Empire.

Like Christian IV, Gustavus Adolphus was subsidized by Cardinal Richelieu, the Chief Minister of Louis XIII of France, and by the Dutch.

Ferdinand II’s suspicion of Wallenstein resumed in 1633, when Wallenstein attempted to arbitrate the differences between the Catholic and Protestant sides. Ferdinand II may have feared that Wallenstein would switch sides, and arranged for his arrest after removing him from command. One of Wallenstein’s soldiers, Captain Devereux, killed him when he attempted to contact the Swedes in the town hall of Eger (Cheb) on 25 February 1634.

From 1630 to 1634, Swedish-led armies drove the Catholic forces back, regaining much of the lost Protestant territory.

After dismissing Wallenstein in 1630, Ferdinand II became dependent on the Catholic League.

France and Bavaria signed the secret Treaty of Fontainebleau (1631), but this was rendered irrelevant by Swedish attacks against Bavaria.

At the Battle of Breitenfeld (1631), Gustavus Adolphus’s forces defeated the Catholic League led by General Tilly.

A year later they met again in another Protestant victory, this time accompanied by the death of Tilly.

• In 1630, Sweden had paid at least 2,368,022 daler for its army of 42,000 men.
• In 1632, it contributed only one-fifth of that (476,439 daler) towards the cost of an army more than three times as large (149,000 men).
• This was possible due to subsidies from France, and the recruitment of prisoners (most of them taken at the Battle of Breitenfeld) into the Swedish army.
• Gustav Adolphus recruited, among others, 20,000 to 30,000 Scottish mercenaries.

With Tilly dead, Ferdinand II returned to the aid of Wallenstein and his large army. Wallenstein marched up to the south, threatening Gustavus Adolphus’s supply chain.

Gustavus Adolphus knew that Wallenstein was waiting for the attack and was prepared, but found no other option.

Wallenstein and Gustavus Adolphus clashed in the Battle of Latzen (1632), where the Swedes prevailed, but Gustavus Adolphus was killed.

In 1634 the Protestant forces, lacking his leadership, were defeated at the First Battle of Nardlingen.

• A year later, Louis XIII died, leaving his five-year-old son Louis XIV on the throne.
  • His chief minister, Cardinal Mazarin, facing the domestic crisis of the Fronde beginning in 1645, began working to end the war.
• In 1645, the Swedish marshal Lennart Torstensson defeated the Imperial army at the Battle of Jankau near Prague,
  • and Louis II de Bourbon, Prince de Condé defeated the Bavarian army in the Second Battle of Nördlingen.
• The last Catholic commander of note, Baron Franz von Mercy, died in the battle.
• On 14 March 1647 Bavaria, Cologne, France and Sweden signed the Truce of Ulm.
• In 1648 the Swedes (commanded by Marshal Carl Gustaf Wrangel) and the French (led by Turenne and Condé) defeated the Imperial army at the Battle of Zusmarshausen and Lens.

These results left only the Imperial territories of Austria safely in Habsburg hands.

France, although overwhelmingly Roman Catholic, was a rival of the Holy Roman Empire and Spain.

Cardinal Richelieu, the Chief Minister of King Louis XIII of France, felt that the Habsburgs were too powerful, since they held a number of territories on France’s eastern border, including portions of the Netherlands.

Richelieu had already begun intervening indirectly in the war in January 1631, when the French diplomat Hercules de Charnace signed the Treaty of Bärwalde with Gustavus Adolphus, by which France agreed to support the Swedes with 1,000,000 livres each year in return for a Swedish promise to maintain an army in Germany against the Habsburgs.

The treaty also stipulated that Sweden would not conclude a peace with the Holy Roman Emperor without first receiving France’s approval.

• A delay in the enforcement of the Edict of Restitution for 40 years and allowing Protestant rulers to retain secularized bishoprics held by them in 1627. This protected the Lutheran rulers of northeastern Germany, but not those of the south and west (whose lands had been occupied by the Imperial or League armies prior to 1627)
• Union of the army of the Emperor and the armies of the German states into a single army of the Holy Roman Empire
  • (although Johann Georg of Saxony and Maximillian of Bavaria kept, as a practical matter, independent command of their forces, now nominally components of the “Imperial” army).
• The forbidding of German princes from establishing alliances amongst themselves or with foreign powers.
• The granting of amnesty to any ruler who had taken up arms against the Emperor after the arrival of the Swedes in 1630.

This treaty failed to satisfy France, however, because of the renewed strength it granted the Habsburgs. France then entered the conflict, beginning the final period of the Thirty Years’ War.

After the Swedish rout at Nardlingen in September 1634 and the Peace of Prague in 1635, as Sweden’s ability to continue the war alone appeared doubtful, Richelieu made the decision to enter into direct war against the Habsburgs.

France declared war on Spain in May 1635 and the Holy Roman Empire in August 1636, opening offensives against the Habsburgs in Germany and the Low Countries.

Although a Catholic clergyman himself, Cardinal Richelieu allied France with the Protestants.

French military efforts met with disaster, and the Spanish counter-attacked, invading French territory.

The Imperial general Johann von Werth and Spanish commander Cardinal Ferdinand Habsburg ravaged the French provinces of Champagne, Burgundy and Picardy, and even threatened Paris in 1636 before being repulsed by Bernhard of Saxe-Weimar.

Bernhard’s victory in the Battle of Compiagne pushed the Habsburg armies back towards the borders of France. Widespread fighting ensued, with neither side gaining an advantage.

French General Louis II de Bourbon, 4th Prince de Condé, Duc d’Enghien,

The Great Condé defeated the Spanish at the Battle of Rocroi in 1643, which led to negotiations.

At them were Ferdinand III, Holy Roman Emperor, the French, the Spanish, the Dutch, the Swiss, the Swedes, the Portuguese and representatives of the Pope.

The Peace of Westphalia of 1648 was the result.

Soon afterward the Bohemian conflict spread through all of Greater Bohemia, which was effectively Bohemia, Silesia, Lusatia and Moravia.

Moravia was already embroiled in a conflict between Catholics and Protestants. The religious conflict eventually spread across the whole continent of Europe, involving France, Sweden, and a number of other countries.

Had the Bohemian rebellion remained a local conflict, the war could have been over in fewer than thirty months. However, the death of Emperor Matthias emboldened the rebellious Protestant leaders, who had been on the verge of a settlement.

The weaknesses of both Ferdinand (now officially on the throne after the death of Emperor Matthias) and of the Bohemians themselves led to the spread of the war to western Germany.

Ferdinand was compelled to call on his nephew, King Philip IV of Spain, for assistance.

The Bohemians, desperate for allies against the Emperor, applied to be admitted into the Protestant Union, which was led by their original candidate for the Bohemian throne, the Calvinist Frederick V, Elector Palatine.

The Bohemians hinted that Frederick would become King of Bohemia if he allowed them to join the Union and come under its protection. However, similar offers were made by other members of the Bohemian Estates to the Duke of Savoy, the Elector of Saxony, and the Prince of Transylvania.

The Austrians, who seemed to have intercepted every letter leaving Prague, made these duplicities public. This unraveled much of the support for the Bohemians, particularly in the court of Saxony.

• They were joined in the revolt by much of Upper Austria, whose nobility was then chiefly Lutheran and Calvinist.
• Lower Austria revolted soon after and in 1619, Count Thurn led an army to the walls of Vienna itself.
• In the east, the Protestant Prince of Transylvania led a spirited campaign into Hungary with the support of the Ottoman Sultan.
• The Emperor, who had been preoccupied with the Uzkok War, hurried to reform an army to stop the Bohemians and their allies from entirely overwhelming his country.

The Bohemian Revolt Period: 1618–1622

Frederick V, Elector Palatine as King of Bohemia, painted by Gerrit von Honthorst in 1634, two years after the subject’s death.

Without heirs, Emperor Matthias sought to assure an orderly transition during his lifetime by having his dynastic heir (the fiercely Catholic, Ferdinand of Styria, later Ferdinand II, Holy Roman Emperor) elected to the separate royal thrones of Bohemia and Hungary.

Some of the Protestant leaders of Bohemia feared they would be losing the religious rights granted to them by Emperor Rudolf II in his letter of majesty. They preferred the Protestant Frederick V, elector of the Palatinate (successor of Frederick IV, the creator of the League of Evangelical Union).

However, other Protestants supported the stance taken by the Catholics[citation needed] and, in 1617, Ferdinand was duly elected by the Bohemian Estates to become the Crown Prince, and automatically upon the death of Matthias, the next King of Bohemia.

The king-elect then sent two Catholic councilors (Vilem Slavata of Chlum and Jaroslav Borzita of Martinice) as his representatives to Hradčany castle in Prague in May 1618. Ferdinand had wanted them to administer the government in his absence.

According to legend, the Bohemian Hussites suddenly seized them, subjected them to a mock trial, and threw them out of the palace window, which was some 50 feet off the ground. Remarkably, they survived unharmed.

The Catholic version of the story claims that angels appeared and carried them to safety, while the Protestant version says that they landed in a pile of manure, which saved their lives.[9]

This event, known as the Second Defenestration of Prague, is what started the Bohemian Revolt.

• Estimates of civilian casualties of up to thirty percent of the population of Germany are now treated with caution.
• The mortality rate was perhaps closer to 15 to 20 percent, with deaths due to armed conflict, famine and disease.
• Much of the destruction of civilian lives and property was caused by the cruelty and greed of mercenary soldiers many of whom were rich commanders and poor soldiers.
• The war caused serious dislocations to both the economies and populations of central Europe, but may have done no more than seriously exacerbate changes that had begun earlier.
• Pestilence of several kinds raged among combatants and civilians in Germany and surrounding lands from 1618 to 1648.

Many features of the war spread disease. These included:

• troop movements,
• the influx of soldiers from foreign countries,
• and the shifting locations of battle fronts.
• In addition, the displacement of civilian populations
• and the overcrowding of refugees into cities led to both disease and famine.

Information about numerous epidemics is generally found in local chronicles, such as parish registers and tax records, that are often incomplete and may be exaggerated. The chronicles do show that epidemic disease was not a condition exclusive to war time, but was present in many parts of Germany for several decades prior to 1618.

However, when the Danish and imperial armies met in Saxony and Thuringia during 1625 and 1626, disease and infection in local communities increased. Local chronicles repeatedly referred to “head disease”, “Hungarian disease”, and a “spotted” disease identified as typhus.

After the Mantuan War, between France and the Habsburgs in Italy, the northern half of the Italian peninsula was in the throes of a bubonic plague epidemic (see Italian Plague of 1629–1631).

During the unsuccessful siege of Nuremberg, in 1632, civilians and soldiers in both the Swedish and imperial armies succumbed to typhus and scurvy.

Two years later, as the imperial army pursued the defeated Swedes into southwest Germany, deaths from epidemics were high along the Rhine River.

Bubonic plague continued to be a factor in the war. Beginning in 1634, Dresden, Munich, and smaller German communities such as Oberammergau recorded large numbers of plague casualties.

In the last decades of the war, both typhus and dysentery had become endemic in Germany.

The War can be divided into four major phases:

• the Bohemian Revolt,
• the Danish intervention,
• the Swedish intervention, and
• the French intervention.

One result of the war was the enshrinement of a Germany divided among many territories—all of which, despite their membership in the Empire, won de facto sovereignty.

This significantly hampered the power of the Holy Roman Empire and decentralized German power.

The Thirty Years’ War rearranged the previous structure of power.

The conflict made Spain’s military and political decline visible.

While Spain was preoccupied with fighting in France, Portugal — which had been under personal union with Spain for 60 years — acclaimed John IV of Braganza as king in 1640, and the House of Braganza became the new dynasty of Portugal (see Portuguese Restoration War, for further information).

Meanwhile, Spain was finally forced to accept the independence of the Dutch Republic in 1648, ending the Eighty Years’ War.

With Spain weakening, France became the dominant power in Europe, an outcome confirmed by its victory in the subsequent Franco-Spanish War.

From 1643–45, during the last years of the Thirty Years’ War, Sweden and Denmark fought the Torstenson War. The result of that conflict and the conclusion of the great European war at the Peace of Westphalia in 1648 helped establish post-war Sweden as a force in Europe.

The war had a few other, more subtle consequences:

The Thirty Years’ War marked the last major religious war in mainland Europe, ending large-scale religious bloodshed in 1648. There were other religious conflicts in the years to come, but no great wars.

The destruction caused by mercenary soldiers defied description (see Schwedentrunk). The war did much to end the age of mercenaries that had begun with the first Landsknechts, and ushered in the age of well-disciplined national armies.

• Count Bucquoy, the commander of the Imperial army, defeated the forces of the Protestant Union led by Count Mansfeld at the Battle of Sablat, on 10 June 1619.
  • This cut off Count Thurn’s communications with Prague, and he was forced to abandon his siege of Vienna.
  • The Battle of Sablat also cost the Protestants an important ally—Savoy, long an opponent of Habsburg expansion.
    • Savoy had already sent considerable sums of money to the Protestants and even sent troops to garrison fortresses in the Rhineland.
    • The capture of Mansfeld’s field chancery revealed the Savoyards’ involvement and they were forced to bow out of the war.
• In spite of Sablat, Count Thurn’s army continued to exist as an effective force, and Mansfeld managed to reform his army further north in Bohemia.
• The Estates of Upper and Lower Austria, still in revolt, signed an alliance with the Bohemians in early August.

On 17 August 1619 Ferdinand was officially deposed as King of Bohemia and was replaced by the Palatine Elector Frederick V.

In Hungary, even though the Bohemians had reneged on their offer of their crown, the Transylvanians continued to make surprising progress. They succeeded in driving the Emperor’s armies from that country by 1620.

The edicts agreed upon during the signing of the Peace of Westphalia were instrumental in laying the foundations for what are even today considered the basic tenets of the sovereign nation-state.

• Aside from establishing fixed territorial boundaries for many of the countries involved in the ordeal (as well as for the newer ones created afterwards), the Peace of Westphalia changed the relationship of subjects to their rulers.
  • In earlier times, people had tended to have overlapping political and religious loyalties.
  • Now, it was agreed that the citizenry of a respective nation were subjected first and foremost to the laws and whims of their own respective government rather than to those of neighbouring powers, be they religious or secular.