The Oñate treaty of 6 June 1617 was a secret treaty between the Austrian and Spanish branches of the

House of Habsburg The House of Habsburg (; ), also known as the House of Austria, was one of the most powerful Dynasty, dynasties in the history of Europe and Western civilization. They were best known for their inbreeding and for ruling vast realms throughout ...

. The senior Habsburg branch of Spanish king Philip III reached an agreement with the junior Habsburg branch of Austrian archduke Ferdinand II concerning allocation of key holdings still in dispute following the division of the House of Habsburg. Spanish Philip III agreed that Austrian Ferdinand II should be the only Habsburg to contend to be king of

Bohemia Bohemia ( ; ; ) is the westernmost and largest historical region of the Czech Republic. In a narrow, geographic sense, it roughly encompasses the territories of present-day Czechia that fall within the Elbe River's drainage basin, but historic ...

and

Hungary Hungary is a landlocked country in Central Europe. Spanning much of the Pannonian Basin, Carpathian Basin, it is bordered by Slovakia to the north, Ukraine to the northeast, Romania to the east and southeast, Serbia to the south, Croatia and ...

, allowing Ferdinand II to focus Austrian resources against estates in those two kingdoms who disputed the Habsburg right to inherit the titles from his childless cousin, Matthias of Habsburg, the reigning king and the

Holy Roman Emperor The Holy Roman Emperor, originally and officially the Emperor of the Romans (disambiguation), Emperor of the Romans (; ) during the Middle Ages, and also known as the Roman-German Emperor since the early modern period (; ), was the ruler and h ...

. In turn, Ferdinand II granted Philip III undisputed reign of Habsburg territories along the " Spanish Road", a loosely connected string of Habsburg territories that ranged from upper Italy, through

Alsace Alsace (, ; ) is a cultural region and a territorial collectivity in the Grand Est administrative region of northeastern France, on the west bank of the upper Rhine, next to Germany and Switzerland. In January 2021, it had a population of 1,9 ...

and the

Free County of Burgundy The Free County of Burgundy (; ) was a medieval and early modern feudal polity ruled by a count from 982 to 1678. It became known as Franche-Comté (the ''Free County''), and was located in the modern region of Franche-Comté. It belonged to t ...

, to the

Spanish Netherlands The Spanish Netherlands (; ; ; ) (historically in Spanish: , the name "Flanders" was used as a '' pars pro toto'') was the Habsburg Netherlands ruled by the Spanish branch of the Habsburgs from 1556 to 1714. They were a collection of States of t ...

, securing the main Spanish supply route in the

Eighty Years' War The Eighty Years' War or Dutch Revolt (; 1566/1568–1648) was an armed conflict in the Habsburg Netherlands between disparate groups of rebels and the Spanish Empire, Spanish government. The Origins of the Eighty Years' War, causes of the w ...

(or Dutch War of Independence) against the Protestant Dutch. The agreement was named after Iñigo de Oñate, the Spanish ambassador in

Vienna Vienna ( ; ; ) is the capital city, capital, List of largest cities in Austria, most populous city, and one of Federal states of Austria, nine federal states of Austria. It is Austria's primate city, with just over two million inhabitants. ...

, who negotiated its final version.

Background

In 1612, Rudolph II, Holy Roman Emperor, died and was succeeded by his brother

Matthias Matthias is a name derived from the Greek Ματθαίος, in origin similar to Matthew. Notable people Notable people named Matthias include the following: Religion * Saint Matthias, chosen as an apostle in Acts 1:21–26 to replace Judas Isca ...

.Schormann (2004), p. 23 Since Matthias and the other archdukes of the main branch of the Austrian Habsburgs were childless, they agreed to transfer succession over their lands to the

Styria Styria ( ; ; ; ) is an Austrian Federal states of Austria, state in the southeast of the country. With an area of approximately , Styria is Austria's second largest state, after Lower Austria. It is bordered to the south by Slovenia, and cloc ...

n branch of the Habsburgs, thus effectively agreeing on the succession of Ferdinand II. The agreement amongst the Austrian Habsburgs was made without regard to King

Philip III of Spain Philip III (; 14 April 1578 – 31 March 1621) was King of Spain and King of Portugal, Portugal (where he is known as Philip II of Portugal) during the Iberian Union. His reign lasted from 1598 until his death in 1621. He held dominion over the S ...

, head of the Spanish Habsburgs, who continued to press his own claims to Holy Roman succession on behalf of his sons. Philip's branch was more senior and more powerful than the Austrian branch of the Habsburgs, and Philip himself asserted a claim to the imperial crown as a grandson of Maximilian II and Charles V. The agreement to transfer succession to the Styrian Habsburgs concerned Holy Roman Emperor Matthias' chief political and religious advisor,

Cardinal Cardinal or The Cardinal most commonly refers to * Cardinalidae, a family of North and South American birds **''Cardinalis'', genus of three species in the family Cardinalidae ***Northern cardinal, ''Cardinalis cardinalis'', the common cardinal of ...

Melchior Klesl. As head of Matthias' Secret Council, Klesl was working to facilitate a reconciliation between

Catholics The Catholic Church (), also known as the Roman Catholic Church, is the largest Christian church, with 1.27 to 1.41 billion baptized Catholics worldwide as of 2025. It is among the world's oldest and largest international institut ...

and

Protestants Protestantism is a branch of Christianity that emphasizes Justification (theology), justification of sinners Sola fide, through faith alone, the teaching that Salvation in Christianity, salvation comes by unmerited Grace in Christianity, divin ...

in Austria,Altmann (1992), col. 42-45 hoping to prevent a continued paralysis of the

Holy Roman Empire The Holy Roman Empire, also known as the Holy Roman Empire of the German Nation after 1512, was a polity in Central and Western Europe, usually headed by the Holy Roman Emperor. It developed in the Early Middle Ages, and lasted for a millennium ...

's institutions: the Reichstag was unable to convene in 1608 and 1613, and the common ''Türkenhilfe'' defense against the Ottoman threat was at risk. Cardinal Klesl knew that Ferdinand II favoured the

Counter-Reformation The Counter-Reformation (), also sometimes called the Catholic Revival, was the period of Catholic resurgence that was initiated in response to, and as an alternative to or from similar insights as, the Protestant Reformations at the time. It w ...

, which aimed to address some of the Church's institutional problems that had been raised by the Protestant noblemen whose support was instrumental to the Holy Roman Empire's operations.Press (1991), p. 189

Habsburg terms

Philip's envoys at the court of the

were Baltasar de Zúñiga and

Íñigo Vélez de Guevara, 7th Count of Oñate Inigo is a masculine given name deriving from the Castilian Spanish, Castilian rendering (Íñigo) of the medieval Basque language, Basque name Eneko (given name), Eneko. Ultimately, the name means "my little (man)". While mostly seen among the ...

.Kampmann (2008), pp. 8, 10 Philip III was willing to accept Ferdinand II as successor of Matthias if certain conditions were met. Philip's greater priority was the

and his desire to secure the so-called Spanish Road, a land route connecting the Spanish possessions in northern Italy with the

.Kampmann (2008), p. 8 The sea route to the Spanish Netherlands was insecure, since much of the

Spanish Armada The Spanish Armada (often known as Invincible Armada, or the Enterprise of England, ) was a Spanish fleet that sailed from Lisbon in late May 1588, commanded by Alonso de Guzmán, Duke of Medina Sidonia, an aristocrat without previous naval ...

had been lost and the

Scheldt The Scheldt ( ; ; ) is a river that flows through northern France, western Belgium, and the southwestern part of Netherlands, the Netherlands, with its mouth at the North Sea. Its name is derived from an adjective corresponding to Old Englis ...

river was blocked by the

Dutch Republic The United Provinces of the Netherlands, commonly referred to in historiography as the Dutch Republic, was a confederation that existed from 1579 until the Batavian Revolution in 1795. It was a predecessor state of the present-day Netherlands ...

. While these setbacks had caused Philip to agree to a suspension of hostilities in Europe (the

Twelve Years' Truce The Twelve Years' Truce was a ceasefire during the Eighty Years' War between Habsburg Spain, Spain and the Dutch Republic, agreed in Antwerp on 9 April 1609 and ended on 9 April 1621. While European powers like Kingdom of France, France began tre ...

), the Eighty Years' War was still raging in the colonies and Philip intended to resume hostilities in the European theatre rather than accept the peace conditions proposed by the Dutch Republic. Philip also wanted to strengthen his position in Italy by acquiring principalities around its

Duchy of Milan The Duchy of Milan (; ) was a state in Northern Italy, created in 1395 by Gian Galeazzo Visconti, then the lord of Milan, and a member of the important Visconti of Milan, Visconti family, which had been ruling the city since 1277. At that time, ...

and by gaining direct access to the

Mediterranean Sea The Mediterranean Sea ( ) is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean basin and almost completely enclosed by land: on the east by the Levant in West Asia, on the north by Anatolia in West Asia and Southern Eur ...

via towns like Finale Ligure, allowing it to bypass the

Republic of Genoa The Republic of Genoa ( ; ; ) was a medieval and early modern Maritime republics, maritime republic from the years 1099 to 1797 in Liguria on the northwestern Italy, Italian coast. During the Late Middle Ages, it was a major commercial power in ...

.Kohler (1990), p. 23 Preliminary terms were agreed between Philip and Ferdinand in January 1617, calling for the cession of several Holy Roman fiefdoms in Italy, but did not initially include

. The treaty was concluded on 29 July 1617. Philip III agreed to renounce his claims to the thrones of

and

,Kampmann (2008), p. 10; Kohler (1990), p. 23 so long as the princes of the

Kingdom of Germany The Kingdom of Germany or German Kingdom ( 'kingdom of the Germans', 'German kingdom', "kingdom of Germany", ) was the mostly Germanic language-speaking East Frankish kingdom, which was formed by the Treaty of Verdun in 843. The king was elec ...

did elect Ferdinand II as ruler of the

upon the death of Emperor Matthias. In return, Ferdinand II promised Philip III the town of Finale Ligure, the Principality of Piombino (both of which were already occupied by Spain), as well as cession of Austrian Habsburg rights to Ortenau and

. The Spanish and Austrian Habsburgs kept the Oñate treaty secret from Cardinal Klesl.

Implementation and consequences

With support of Maximilian III, Archduke of Austria,Press (1991), p. 190 and no opposition from Philip III of Spain, Ferdinand II managed to win the Bohemian and Hungarian crowns in 1617 and 1618, respectively.Schormann (2004), p. 24 This placed Ferdinand in a strong position to win any future

election An election is a formal group decision-making process whereby a population chooses an individual or multiple individuals to hold Public administration, public office. Elections have been the usual mechanism by which modern representative d ...

for

. On 20 May 1618, Klesl, who continued to promote a Catholic-Protestant rapprochement, was arrested by Ferdinand II and Maximilian III. Holy Roman Emperor Matthias died on 20 March 1619. The Bohemian estates turned against Ferdinand II, and on 26 and 27 August 1619 elected Frederick V, Elector Palatine, the leader of the Protestants in the Holy Roman Empire, as the new "winter king" of Bohemia.Kohler (1990), p. 33 On the following day, Ferdinand II was elected

by the other princes of the

. The events in Bohemia resulted in mobilization of the German Catholic League, and with Spanish support, Ferdinand II defeated the Bohemian estates and expelled the "winter king" in the

Battle of White Mountain The Battle of White Mountain (; ) was an important battle in the early stages of the Thirty Years' War. It led to the defeat of the Bohemian Revolt and ensured Habsburg control for the next three hundred years. It was fought on 8 November 16 ...

on 8 November 1620.

Sources

References

Bibliography

* * * * * {{DEFAULTSORT:Onate Treaty 1617 treaties 1617 in the Habsburg monarchy 1617 in Spain 17th century in Bohemia 1617 in law Eighty Years' War Matthias, Holy Roman Emperor Ferdinand II, Holy Roman Emperor Treaties of the Habsburg monarchy Treaties of Spain Habsburg monarchy–Spain relations Philip III of Spain Thirty Years' War treaties Spanish Empire in Europe