The Peace of Westphalia (German: Westfälischer Friede) was a series of peace treaties signed between May and October 1648 in the Westphalian cities of Osnabrück and Münster, largely ending the European wars of religion, including the Thirty Years' War. The treaties of Westphalia brought to an end a calamitous period of European history which caused the deaths of approximately eight million people. Scholars have identified Westphalia as the beginning of the modern international system, based on the concept of Westphalian sovereignty, though this interpretation has been seriously challenged.
The negotiation process was lengthy and complex. Talks took place in two different cities, as each side wanted to meet on territory under its own control. A total of 109 delegations arrived to represent the belligerent states, but not all delegations were present at the same time. Three treaties were signed to end each of the overlapping wars: the Peace of Münster, the Treaty of Münster, and the Treaty of Osnabrück. These treaties ended the Thirty Years' War (1618–1648) in the Holy Roman Empire, with the Habsburgs and their Catholic allies on one side, battling the Protestant powers (Sweden, Denmark, Dutch, and Holy Roman principalities) allied with France (Catholic but anti-Habsburg). The treaties also ended the Eighty Years' War (1568–1648) between Spain and the Dutch Republic, with Spain formally recognising the independence of the Dutch.
The Peace of Westphalia established the precedent of peace established by diplomatic congress. A new system of political order arose in central Europe, based upon peaceful coexistence among sovereign states. Inter-state aggression was to be held in check by a balance of power, and a norm was established against interference in another state's domestic affairs. As European influence spread across the globe, these Westphalian principles, especially the concept of sovereign states, became central to international law and to the prevailing world order.
|Peace of Westphalia|
|Treaties of Osnabrück and Münster|
The Ratification of the Treaty of Münster, 15 May 1648 (1648) by Gerard ter Borch
|Signed||15 May – 24 October 1648|
|Location||Osnabrück and Münster, Westphalia, Holy Roman Empire|
Peace negotiations between France and the Habsburgs began in Cologne in 1641. These negotiations were initially blocked by Cardinal Richelieu of France, who insisted on the inclusion of all his allies, whether fully sovereign countries or states within the Holy Roman Empire. In Hamburg and Lübeck, Sweden and the Holy Roman Empire negotiated the Treaty of Hamburg with the intervention of Richelieu. The Holy Roman Empire and Sweden declared the preparations of Cologne and the Treaty of Hamburg to be preliminaries of an overall peace agreement.
In Münster, negotiations took place between the Holy Roman Empire and France, as well as between the Dutch Republic and Spain. Münster had been, since its re-Catholicisation in 1535, a strictly mono-denominational community. It housed the Chapter of the Prince-Bishopric of Münster. Only Roman Catholic worship was permitted, while Calvinism and Lutheranism were prohibited.
Sweden preferred to negotiate with the Holy Roman Empire in Osnabrück, controlled by the Protestant forces. Osnabrück was a bidenominational Lutheran and Catholic city, with two Lutheran churches and two Catholic churches. The city council was exclusively Lutheran, and the burghers mostly so, but the city also housed the Catholic Chapter of the Prince-Bishopric of Osnabrück and had many other Catholic inhabitants. Osnabrück had been subjugated by troops of the Catholic League from 1628 to 1633 and then taken by Lutheran Sweden.
The peace negotiations had no exact beginning and ending, because the 109 delegations never met in a plenary session. Instead, various delegations arrived between 1643 and 1646 and left between 1647 and 1649. The largest number of diplomats were present between January 1646 and July 1647.
Three separate treaties constituted the peace settlement.
The power asserted by Ferdinand III was stripped from him and returned to the rulers of the Imperial States. The rulers of the Imperial States could henceforth choose their own official religions. Catholics and Protestants were redefined as equal before the law, and Calvinism was given legal recognition as an official religion. The independence of the Dutch Republic, which practiced religious toleration, also provided a safe haven for European Jews.
The Holy See was very displeased at the settlement, with Pope Innocent X calling it "null, void, invalid, iniquitous, unjust, damnable, reprobate, inane, empty of meaning and effect for all time" in the bull Zelo Domus Dei.
The main tenets of the Peace of Westphalia were:
The treaties did not entirely end conflicts arising out of the Thirty Years' War. Fighting continued between France and Spain until the Treaty of the Pyrenees in 1659. The Dutch-Portuguese War had begun during the Iberian Union between Spain and Portugal, as part of the Eighty Years' War, and went on until 1663. Nevertheless, the Peace of Westphalia did settle many outstanding European issues of the time.
Scholars of international relations have identified the Peace of Westphalia as the origin of principles crucial to modern international relations, including the inviolability of borders and non-interference in the domestic affairs of sovereign states. This system became known in the literature as Westphalian sovereignty. Although scholars have challenged the association with the Peace of Westphalia, the debate is still structured around the concept of Westphalian sovereignty.
was a leap year starting on Wednesday of the Gregorian calendar and a leap year starting on Saturday of the Julian calendar, the 1648th year of the Common Era (CE) and Anno Domini (AD) designations, the 648th year of the 2nd millennium, the 48th year of the 17th century, and the 9th year of the 1640s decade. As of the start of 1648, the Gregorian calendar was
10 days ahead of the Julian calendar, which remained in localized use until 1923.
1648 has been suggested as possibly the last year in which the overall human population declined, coming towards the end of a broader period of global instability which included the collapse of the Ming dynasty and the Thirty Years' War, the latter of which ended in 1648 with the Peace of Westphalia.Alvise Contarini
Not to be confused with Alvise Contarini (1597–1651), Venetian diplomat who negotiated the Peace of Westphalia.Alvise Contarini (24 October 1601 – 15 January 1684) was the 106th Doge of Venice, reigning from his election on 26 August 1676 until his death seven and a half years later. He was the eighth and final member of the House of Contarini to serve as Doge of Venice (with the first being Domenico I Contarini, who became Doge in 1043).
His reign was largely peaceful, as the Republic of Venice was still recovering from the defeat to the Ottoman Empire in the 1645–69 Cretan War. However, in the last days of Contarini's reign, hostilities with the Ottoman Empire were rekindled once again, and Venice soon entered the Sixth Ottoman-Venetian War, better known as the Morean War (1684–99).Anuschka Tischer
Anuschka Tischer (born 30 July 1968 in Arnsberg, Germany) is a historian at the University of Würzburg. She has been a Robert Bosch Foundation Lecturer for History at the University of Latvia in Riga, and a scientific assistant at the Philipps-Universität in Marburg. A former research fellow for the edition series Acta Pacis Wesphalicae, she has published works on French diplomacy at the Congress of Westphalia and is currently doing work on the Franco-Spanish War of the 1650s.
Tischer earned her M.A. degree on 1992 with her work Magisterarbeit zu den Reformbestrebungen Kaiser Maximilians I. in Heerwesen und Kriegsorganisation des Reichs [Master's thesis on Emperor Maximilian I's attempts to reform the army and military organization of the empire]. She obtained her PhD in 1998 with her Dissertation zum außenpolitischen Wandel von Richelieu zu Mazarin am Beispiel der französischen Diplomatie beim Westfälischen Frieden [Dissertation on the change in foreign policy from Richelieu to Mazarin using the example of French diplomacy at the Peace of Westphalia]. She also wrote Französische Diplomatie und Diplomaten auf dem Westfälischen Friedenskongreß. Außenpolitik unter Richelieu und Mazarin [French diplomacy and diplomats at the peace congress of Westphalia: foreign policy under Richelieu and Mazarin], published in 1999.
Alongside Derek Croxton, she wrote the critically acclaimed The Peace of Westphalia: A Historical Dictionary.Bishopric of Metz
The Bishopric of Metz was a prince-bishopric of the Holy Roman Empire. It was one of the Three Bishoprics that were annexed by France in 1552.
The Bishops of Metz had already ruled over a significant amount of territories within the former Kingdom of Lotharingia, which by the 870 Treaty of Meerssen became a part of East Francia. They had to struggle for their independence from the Dukes of Lorraine, acquired the lands of the Counts of Metz, but had to face the rise of their capital Metz to the status of an Imperial City in 1189. In 1234 the unrest of the Metz citizens forced the bishops to move their residence to Vic-sur-Seille.
In 1357 Emperor Charles IV of Luxembourg again confirmed the bishopric's Imperial immediacy. From the accession of Henri of Lorraine-Vaudémont in 1484 however, the diocese was ruled by bishops from the House of Lorraine, who by their close relations with the House of Valois brought Metz unter the influence of the French crown. By the 1552 Treaty of Chambord, an alliance of revolting Protestant Imperial princes led by Elector Maurice of Saxony promised the overlordship over the Three Bishoprics of Metz, Toul and Verdun to King Henry II of France. Metz was occupied by Henry's troops and annexed by the French crown, finally acknowledged by the Empire in the 1648 Peace of Westphalia.Churches of Peace
The Churches of Peace (Polish: Kościoły Pokoju, German: Friedenskirchen) in Jawor (German: Jauer) and Świdnica (German: Schweidnitz) in Silesia were named after the Peace of Westphalia of 1648.
It permitted the Lutherans of Silesia to build three churches from wood, loam and straw outside the city walls, without steeples and church bells. The construction time was limited to one year. The third Peace church, erected in Głogów (then German Glogau), burned down in 1758.
Since 2001, the two remaining churches are listed as UNESCO World Heritage Sites.Claude de Mesmes, comte d'Avaux
Claude de Mesmes, comte d'Avaux (1595–1650) was a 17th-century French diplomat and public administrator. Richelieu sent him to Venice, Rome, Germany, Sweden, Denmark, and Poland to represent France. In 1635 de Mesmes mediated in the negotiations leading to the Treaty of Stuhmsdorf, which extended the truce between Poland and Sweden. In 1638 he negotiated the Treaty of Hamburg with Sweden. He was plenipotentiary at the Peace of Westphalia and ended his career as Superintendent of Finances.Décapole
The Décapole (Dekapolis or German: Zehnstädtebund) was an alliance formed in 1354 by ten Imperial cities of the Holy Roman Empire in the Alsace region to maintain their rights. It was disbanded in 1679.
In 1354 Emperor Charles IV of Luxembourg ratified the treaty uniting the towns of Haguenau, Colmar, Wissembourg, Turckheim, Obernai, Kaysersberg, Rosheim, Munster, Sélestat and Mulhouse. Hagenau became its capital while the Imperial city of Strasbourg, though venue of the league's diets, remained outside the alliance. The town of Seltz joined the league when it received immediate status in 1357, but had to leave it after its mediatization to the Electorate of the Palatinate in 1414.
The affiliation at first discontinued after Charles' death in 1378, it was, however, re-established in the next year. The ten cities joined the Upper Rhenish Circle in 1500. In 1515, Mulhouse pulled out of the alliance in order to associate with the Old Swiss Confederacy. It was replaced in 1521 by the city of Landau in northern Alsace.The alliance was strongly shaken by the Thirty Years' War which ravaged the region, allowing King Louis XIV of France to conquer the cities according to the 1648 Peace of Westphalia. The signing of the Treaties of Nijmegen in 1679 finally brought an end to the Décapole, when Alsace was annexed by France. Mulhouse remained an independent city and exclave of the Swiss Confederation until in 1798 it was annexed to the French First Republic. Landau together with the Palatinate was given to Bavaria after the 1815 Congress of Vienna.Electorate of Bavaria
The Electorate of Bavaria (German: Kurfürstentum Bayern) was an independent hereditary electorate of the Holy Roman Empire from 1623 to 1806, when it was succeeded by the Kingdom of Bavaria.The Wittelsbach dynasty which ruled the Duchy of Bavaria was the younger branch of the family which also ruled the Electorate of the Palatinate. The head of the elder branch was one of the seven prince-electors of the Holy Roman Empire according to the Golden Bull of 1356, but Bavaria was excluded from the electoral dignity. In 1621, the Elector Palatine Frederick V was put under the imperial ban for his role in the Bohemian Revolt against Emperor Ferdinand II, and the electoral dignity and territory of the Upper Palatinate was conferred upon his loyal cousin, Duke Maximilian I of Bavaria. Although the Peace of Westphalia would create a new electoral title for Frederick V's son, with the exception of a brief period during the War of the Spanish Succession, Maximilian's descendants would continue to hold the original electoral dignity until the extinction of his line in 1777. At that point the two lines were joined in personal union until the end of the Holy Roman Empire. In 1805, after the Peace of Pressburg, the then-elector, Maximilian Joseph, raised himself to the dignity of King of Bavaria, and the Holy Roman Empire was abolished the year after.Heilbronn League
The Heilbronn League was an alliance between Sweden, France, and the Protestant princes in western Germany against the Catholic League during the Thirty Years' War. The treaty forming the League was signed at Heilbronn in Germany on 23 April 1633.
After the death of Gustavus Adolphus of Sweden in 1632 the majority of German states were desperate to achieve peace. Nevertheless, Wallenstein's continued military operations, as well as the diplomatic work carried out by Axel Oxenstierna, Sweden’s first minister, failed to bring about a permanent settlement. Most significantly, the search for a peace that would privilege all of those who signed it ensured the continuance of the war.
It was essential that France took the lead, and provide patronage to their German allies. Together they formed the Heilbronn League, which consisted of the Upper and Lower Rhenish, Swabian and Franconian military circles. Each of the circles was required to provide 2.5 million Reichstaler annually, while the Swedes retained their position as overall military commanders. France also agreed to increase the revenue that it would supply, as the death of Gustavus had resulted in France having a greater influence on the overall military situation.
After the crushing Imperial-Spanish victory of Nördlingen, most of the German Protestant states were compelled to seek peace with the Emperor, who was now ready to come to terms and to relinquish the harshest provisions of the Edict of Restitution. Peace between the Emperor and the majority of German states was achieved at the Peace of Prague. This treaty was signed not only by eastern Protestant states, like Saxony and Brandenburg (which were not parties to the Heillbronn League), but even by many Swedish allies in western Germany. Thus, after the Peace of Prague, the Heilbronn League’s role was virtually over. Legally speaking, this treaty affirmed that German states could not enter in alliance treaties with other states. Swedish influence in the Rhineland theatre evaporated, and in the following years military operations were conducted under French leadership.
A few former League’s members, especially Hesse, continued to fight against the Emperor until the final Peace of Westphalia.Imperial immediacy
Imperial immediacy (German: Reichsfreiheit or Reichsunmittelbarkeit) was a privileged constitutional and political status rooted in German feudal law under which the Imperial estates of the Holy Roman Empire such as Imperial cities, prince-bishoprics and secular principalities, and individuals such as the Imperial knights, were declared free from the authority of any local lord and placed under the direct ("immediate", in the sense of "without an intermediary") authority of the Emperor, and later of the institutions of the Empire such as the Diet (Reichstag), the Imperial Chamber of Justice and the Aulic Council.
The granting of immediacy began in the Early Middle Ages, and for the immediate bishops, abbots and cities, then the main beneficiaries of that status, immediacy could be exacting and often meant being subjected to the fiscal, military and hospitality demands of their overlord, the Emperor. However, with the gradual exit of the Emperor from the centre stage from the mid-13th century onwards, holders of imperial immediacy eventually found themselves vested with considerable rights and powers previously exercised by the emperor.
As confirmed by the Peace of Westphalia in 1648, the possession of imperial immediacy came with a particular form of territorial authority known as territorial superiority (Landeshoheit or superioritas territorialis in German and Latin documents of the time). In today's terms, it would be understood as a limited form of sovereignty.Johann Schop
Johann Schop (ca. 1590 – 1667) was a German violinist and composer, much admired as a musician and a technician, who was a virtuoso and whose compositions for the violin set impressive technical demands for that area at that time. In 1756 Leopold Mozart commented on the difficulty of a trill in a work by Schop, probably composed before 1646.He worked in Hamburg. He published books of violin music in 4 to 6 parts; some of his music was performed at the Peace of Westphalia celebrations.
His melody Werde munter, mein Gemüte of 1641 was used by Johann Sebastian Bach for the chorale movements (6 and 10) of his cantata Herz und Mund und Tat und Leben, BWV 147. The sixth movement is Wohl mir, daß ich Jesum habe, and the tenth movement is Jesu bleibet meine Freude. Under the English title of Jesu, Joy of Man's Desiring Bach's chorale has been arranged for different instruments and has gained wide popularity.Peace of Augsburg
The Peace of Augsburg, also called the Augsburg Settlement, was a treaty between Charles V, Holy Roman Emperor (the predecessor of Ferdinand I), and the Schmalkaldic League, signed in September 1555 at the imperial city of Augsburg. It officially ended the religious struggle between the two groups and made the legal division of Christianity permanent within the Holy Roman Empire, allowing rulers to choose either Lutheranism or Roman Catholicism as the official confession of their state. Calvinism was not allowed until the Peace of Westphalia.Peace of Münster
The Peace of Münster was a treaty between the Lords States General of the United Netherlands and the Spanish Crown, the terms of which were agreed on 30 January 1648. The Treaty is a key event in Dutch history marking formal recognition of the independent Dutch Republic and formed part of the Peace of Westphalia ending the Thirty Years' War and the Eighty Years' War.Peace of Prague (1635)
The Peace of Prague was a peace treaty signed on 30 May 1635 by the Habsburg Emperor Ferdinand II and Elector John George I of Saxony representing most of the Protestant Estates of the Holy Roman Empire. It effectively brought to an end the civil war aspect of the Thirty Years' War; however, the combat actions still carried on due to the continued intervention on German soil by Spain, Sweden, and, from mid-1635, France, until the Peace of Westphalia was concluded in 1648.Swedish Pomerania
Swedish Pomerania (Swedish: Svenska Pommern; German: Schwedisch-Pommern) was a Dominion under the Swedish Crown from 1630 to 1815, situated on what is now the Baltic coast of Germany and Poland. Following the Polish War and the Thirty Years' War, Sweden held extensive control over the lands on the southern Baltic coast, including Pomerania and parts of Livonia and Prussia (dominium maris baltici).
Sweden, present in Pomerania with a garrison at Stralsund since 1628, had gained effective control of the Duchy of Pomerania with the Treaty of Stettin in 1630. At the Peace of Westphalia in 1648 and the Treaty of Stettin in 1653, Sweden received Western Pomerania (German Vorpommern), with the islands of Rügen, Usedom, and Wolin, and a strip of Farther Pomerania (Hinterpommern). The peace treaties were negotiated while the Swedish queen Christina was a minor, and the Swedish Empire was governed by members of the high aristocracy. As a consequence, Pomerania was not annexed to Sweden like the French war gains, which would have meant abolition of serfdom, since the Pomeranian peasant laws of 1616 was practised there in its most severe form. Instead, it remained part of the Holy Roman Empire, making the Swedish rulers Reichsfürsten (imperial princes) and leaving the nobility in full charge of the rural areas and its inhabitants. While the Swedish Pomeranian nobles were subjected to reduction when the late 17th century kings regained political power, the provisions of the peace of Westphalia continued to prevent the pursuit of the uniformity policy in Pomerania until the Holy Roman empire was dissolved in 1806.
In 1679, Sweden lost most of her Pomeranian possessions east of the Oder river in the Treaty of Saint-Germain-en-Laye, and in 1720, Sweden lost her possessions south of the Peene and east of the Peenestrom rivers in the Treaty of Stockholm. These areas were ceded to Brandenburg-Prussia and were integrated into Brandenburgian Pomerania. Also in 1720, Sweden regained the remainder of her dominion in the Treaty of Frederiksborg, which had been lost to Denmark in 1715. In 1814, as a result of the Napoleonic Wars, Swedish Pomerania was ceded to Denmark in exchange for Norway in the Treaty of Kiel, and in 1815, as a result of the Congress of Vienna, transferred to Prussia.Thirty Years' War
The Thirty Years' War was a war fought primarily in Central Europe between 1618 and 1648. One of the most destructive conflicts in human history, it resulted in eight million fatalities not only from military engagements but also from violence, famine, and plague. Casualties were overwhelmingly and disproportionately inhabitants of the Holy Roman Empire, most of the rest being battle deaths from various foreign armies. In terms of proportional German casualties and destruction, it was surpassed only by the period January to May 1945; one of its enduring results was 19th-century Pan-Germanism, when it served as an example of the dangers of a divided Germany and became a key justification for the 1871 creation of the German Empire.Initially a war between various Protestant and Catholic states in the fragmented Holy Roman Empire, it gradually developed into a more general conflict involving most of the European great powers. These states employed relatively large mercenary armies, and the war became less about religion and more of a continuation of the France–Habsburg rivalry for European political pre-eminence.
The war was preceded by the election of the new Holy Roman Emperor, Ferdinand II, who tried to impose religious uniformity on his domains, forcing Roman Catholicism on its peoples. The northern Protestant states, angered by the violation of their rights to choose, which had been granted in the Peace of Augsburg, banded together to form the Protestant Union. Ferdinand II was a devout Roman Catholic and much more intolerant than his predecessor, Rudolf II, who ruled from the largely Protestant city of Prague. Ferdinand's policies were considered strongly pro-Catholic and anti-Protestant.
These events caused widespread fears throughout northern and central Europe, and triggered the Protestant Bohemians living in the then relatively loose dominion of Habsburg Austria (and also with the Holy Roman Empire) to revolt against their nominal ruler, Ferdinand II. After the so-called Defenestration of Prague deposed the Emperor's representatives in Prague, the Protestant estates and Catholic Habsburgs started gathering allies for war. The Protestant Bohemians ousted the Habsburgs and elected the Calvinist Frederick V, Elector of the Rhenish Palatinate as the new king of the Kingdom of Bohemia. Frederick took the offer without the support of the Protestant Union. The southern states, mainly Roman Catholic, were angered by this. Led by Bavaria, these states formed the Catholic League to expel Frederick in support of the Emperor. The Empire soon crushed the perceived Protestant rebellion in the Battle of White Mountain, executing leading Bohemian aristocrats shortly after. Protestant rulers across Europe unanimously condemned the Emperor's action.
After the atrocities committed in Bohemia, Saxony finally gave its support to the Protestant Union and decided to fight back. Sweden, at the time a rising military power, soon intervened in 1630 under its king Gustavus Adolphus, transforming what had been simply the Emperor's attempt to curb the Protestant states into a full-scale war in Europe. Habsburg Spain, wishing to finally crush the Dutch rebels in the Netherlands and the Dutch Republic (which was still a part of the Holy Roman Empire), intervened under the pretext of helping its dynastic Habsburg ally, Austria. No longer able to tolerate the encirclement of two major Habsburg powers on its borders, Catholic France entered the coalition on the side of the Protestants in order to counter the Habsburgs.
The Thirty Years' War devastated entire regions, resulting in high mortality, especially among the populations of the German and Italian states, the Crown of Bohemia, and the Southern Netherlands. Both mercenaries and soldiers in fighting armies traditionally looted or extorted tribute to get operating funds, which imposed severe hardships on the inhabitants of occupied territories. The war also bankrupted most of the combatant powers.
The Dutch Republic enjoyed contrasting fortune; it was removed from the Holy Roman Empire and was able to end its revolt against Spain in 1648 and subsequently enjoyed a time of great prosperity and development, known as the Dutch Golden Age, during which it became one of the world's foremost economic, colonial, and naval powers. The Thirty Years' War ended with the Treaty of Osnabrück and the Treaties of Münster, part of the wider Peace of Westphalia. The war altered the previous political order of European powers. The rise of Bourbon France, the curtailing of Habsburg ambition, and the ascendancy of Sweden as a great power created a new balance of power on the continent, with France emerging from the war strengthened and increasingly dominant in the latter part of the 17th century.Three Bishoprics
The Three Bishoprics (French: les Trois-Évêchés, French pronunciation: [le tʁwazevɛʃe]) constituted a province of pre-revolutionary France consisting of the dioceses of Metz, Verdun, and Toul within the Lorraine region. The three dioceses were Prince-bishoprics of the Holy Roman Empire until they were seized by King Henry II of France between April and June 1552. At the end of the Thirty Years' War, they were officially ceded to France by the 1648 Peace of Westphalia.Treaty of Stettin (1653)
The Treaty of Stettin (German: Grenzrezeß von Stettin) of 4 May 1653 settled a dispute between Brandenburg and Sweden, who both claimed succession in the Duchy of Pomerania after the extinction of the local House of Pomerania during the Thirty Years' War. Brandenburg's claims were based on the Treaty of Grimnitz (1529), while Sweden's claims were based on the Treaty of Stettin (1630). The parties had agreed on a partition of the Swedish-held duchy in the Peace of Westphalia (1648), and with the Treaty of Stettin determined the actual border between the partitions. Western Pomerania became Swedish Pomerania, Farther Pomerania became Brandenburgian Pomerania.Westphalian sovereignty
Westphalian sovereignty, or state sovereignty, is the principle in international law that each state has exclusive sovereignty over its territory. The principle underlies the modern international system of sovereign states and is enshrined in the United Nations Charter, which states that "nothing should authorise intervention in matters essentially within the domestic jurisdiction of any state." According to the idea, every state, no matter how large or small, has an equal right to sovereignty. Political scientists have traced the concept to the Peace of Westphalia (1648), which ended the Thirty Years' War. The principle of non-interference was further developed in the 18th century. The Westphalian system reached its peak in the 19th and 20th centuries, but it has faced recent challenges from advocates of humanitarian intervention.
Treaties of the Thirty Years' War (1618–1648)