Hugo Grotius (10 April 1583 – 28 August 1645), also known as Huig de Groot, Hugo Grocio or Hugo de Groot, was a jurist in the Dutch Republic. With Francisco de Vitoria and Alberico Gentili he laid the foundations for international law, based on natural law. He was also a philosopher, theologian, Christian apologist, playwright, and poet.

Grotius's influence on international law is paramount, and is acknowledged by, for instance, the American Society of International Law, which since 1999 holds an annual series of Grotius Lectures. Additionally, his contributions to Arminian theology provided the seeds for later Arminian based movements, such as Methodism and Pentecostalism and he is acknowledged as a significant figure in the Arminianism - Calvinism debate.

Born in Delft during the Dutch Revolt, Hugo was the first child of Jan de Groot and Alida van Overschie. His father was a man of learning, once having studied with the eminent Justus Lipsius at Leiden, as well as of political distinction, and he groomed his son from an early age in a traditional humanist and Aristotelian education. A prodigious learner, Hugo entered the University of Leiden when he was just eleven years old. There he studied with some of the most acclaimed intellectuals in northern Europe, including Franciscus Junius, Joseph Justus Scaliger, and Rudolph Snellius. At age sixteen he published his first book: a scholarly edition of the late antique author Martianus Capella's work on the seven liberal arts, Martiani Minei Felicis Capellæ Carthaginiensis viri proconsularis Satyricon, in quo De nuptiis Philologiæ & Mercurij libri duo, & De septem artibus liberalibus libri singulares. Omnes, & emendati, & Notis, siue Februis Hug. Grotii illustrati.

In Holland, Grotius earned an appointment as advocate to The Hague in 1599 and then as official historiographer for the States of Holland in 1601. His first occasion to write systematically on issues of international justice came in 1604, when he became involved in the legal proceedings following the seizure by Dutch merchants of a Portuguese carrack and its cargo in the Singapore Strait.

The Dutch were at war with Spain and Portugal when the loaded merchant ship Santa Catarina, a Portuguese carrack, was captured by captain Jacob van Heemskerk off present day Singapore in 1603. Heemskerk was employed with the United Amsterdam Company (part of the Dutch East India Company), and though he did not have authorization from the company or the government to initiate the use of force, many shareholders were eager to accept the riches that he brought back to them. Not only was the legality of keeping the prize questionable under Dutch statute, but a faction of shareholders (mostly Mennonite) in the Company also objected to the forceful seizure on moral grounds, and of course, the Portuguese demanded the return of their cargo. The scandal led to a public judicial hearing and a wider campaign to sway public (and international) opinion. It was in this wider context that representatives of the Company called upon Grotius to draft a polemical defence of the seizure.

The result of Grotius' efforts in 1604 - 1605 was a long, theory laden treatise that he provisionally entitled De Indis (On the Indies). Grotius sought to ground his defense of the seizure in terms of the natural principles of justice. In this, he had cast a net much wider than the case at hand; his interest was in the source and ground of war's lawfulness in general. The treatise was never published in full during Grotius' lifetime, perhaps because the court ruling in favor of the Company preempted the need to garner public support. The manuscript was not made public until it was uncovered from Grotius' estate in 1864 and published under the title, De Jure Praedae (On the Right of Capture). The principles that Grotius developed there, however, laid the basis for his mature work on international justice, De jure belli ac pacis, and in fact one chapter of the earlier work did make it to the press in the form of the influential pamphlet, Mare Liberum.

In The Free Sea (Mare Liberum, published 1609) Grotius formulated the new principle that the sea was international territory and all nations were free to use it for seafaring trade. Grotius, by claiming 'free seas' (Freedom of the seas), provided suitable ideological justification for the Dutch breaking up of various trade monopolies through its formidable naval power (and then establishing its own monopoly).

England, competing fiercely with the Dutch for domination of world trade, opposed this idea and claimed That the Dominion of the British Sea, or That Which Incompasseth the Isle of Great Britain, is, and Ever Hath Been, a Part or Appendant of the Empire of that Island. William Welwod, a Scottish jurist who was the first to formulate the laws of the sea in the English language, argued against Grotius' Mare Liberum in An Abridgement of All Sea - Lawes (1613), eliciting a response from Grotius around 1615 under the title Defensio capitis quinti Maris Liberi oppugnati a Gulielmo Welwodo ("Defense of chapter five of the 'Free Oceans,' opposed by William Welwod"). In Mare clausum (1635) John Selden endeavoured to prove that the sea was in practice virtually as capable of appropriation as terrestrial territory.

As conflicting claims grew out of the controversy, maritime states came to moderate their demands and base their maritime claims on the principle that it extended seawards from land. A workable formula was found by Cornelius Bynkershoek in his De dominio maris (1702), restricting maritime dominion to the actual distance within which cannon range could effectively protect it. This became universally adopted and developed into the three - mile limit.

The dispute would eventually have important economic implications. The Dutch Republic supported the idea of free trade (even though it imposed a special trade monopoly on nutmeg and cloves in the Moluccas). England adopted the Act of Navigation (1651), forbidding any goods from entering England except on English ships. The Act subsequently led to the First Anglo - Dutch War (1652 – 1654).

Aided by his continued association with Van Oldenbarnevelt, Grotius made considerable advances in his political career, being retained as Oldenbarnevelt's resident advisor in 1605, Advocate General of the Fisc of Holland, Zeeland and Friesland in 1607, and then as Pensionary of Rotterdam (the equivalent of a mayoral office) in 1613. In 1608 he married Maria van Reigersbergen, with whom he would have eight children (four surviving beyond youth) and who would be invaluable in helping him and the family to weather the storm to come.

In these years a great theological controversy broke out between the chair of theology at Leiden Jacobus Arminius and his followers (who are called Arminians or Remonstrants) and the strongly Calvinist theologian, Franciscus Gomarus whose supporters are termed Gomarists or Counter - Remonstrants. Leiden University "was under the authority of the States of Holland - they were responsible, among other things, for the policy concerning appointments at this institution, which was governed in their name by a board of Curators - and, in the final instance, the States were responsible for dealing with any cases of heterodoxy among the professors." The domestic dissension resulting over Arminius' professorship was overshadowed by the continuing war with Spain, and the professor died in 1609 on the eve of the Twelve Years' Truce. The new peace would move the people's focus to the controversy and Arminius' followers.

In 1610, several months after the death of their leader, the Arminians issued a 'Remonstrance' declaring their doctrinal differences with the mainstream Reformed doctrines of salvation, most often associated with the Protestant Reformer John Calvin, but also held by most Reformed pastors and theologians throughout Europe. They had particular problems with the Belgic Confession, art. 16, on eternal election and reprobation. The Remonstrants did not reject the doctrines of election or predestination, as is often assumed, but rather redefined them so that the decisive factor in a person's salvation is not God's inscrutable decree, but the individual's faith, which is eternally foreknown by God. According to Arminius and the Remonstrants, God decrees to elect all who meet the condition of faith.

The controversy expanded when the Remonstrant theologian Conrad Vorstius was appointed to replace Jacobus Arminius as the theology chair at Leiden. Vorstius was soon seen by Counter - Remonstrants as moving beyond the teachings of Arminius into Socinianism and accused of teaching irreligion. Leading the call for Vorstius' removal was theology professor Sibrandus Lubbertus. On the other side Johannes Wtenbogaert (a Remonstrant leader) and Johan van Oldenbarnevelt, Grand Pensionary of Holland had strongly promoted the appointment of Vorstius and began to defend their actions. Gomarus resigned his professorship at Leiden in protest that Vorstius was not removed. The Counter - Remonstrants were also supported in their opposition by King James I of England "who thundered loudly against the Leiden nomination and gaudily depicted Vorstius as a horrid heretic. He ordered his books to be publicly burnt in London, Cambridge, and Oxford, and he exerted continual pressure through his ambassador in the Hague, Ralph Winwood, to get the appointment cancelled." James began to shift his confidence from Oldenbarnevelt towards Maurice.

Grotius joined the controversy by defending the civil authorities power to appoint (independent of the wishes of religious authorities) whomever they wished to a university's faculty. He did this by writing Ordinum Pietas "a pamphlet... directed against an opponent, the Calvinist Franeker professor Lubbertus; it was ordered by Grotius' masters the States of Holland, and thus written for the occasion - though Grotius may already have had plans for such a book." The work is twenty - seven pages long, is "polemical and acrimonious" and only two - thirds of it speaks directly about ecclesiastical politics (mainly of synods and offices). The work met with a violent reaction from the Counter - Remostrants, and "It might be said that all Grotius' next works until his arrest in 1618 form a vain attempt to repair the damage done by this book." Grotius would later write De Satisfactione aiming "at proving that the Arminians are far from being Socinians."

Led by Oldenbarnevelt, the States of Holland took an official position of religious toleration towards Remostrants and Counter - Remostrants. Grotius, (who acted during the controversy first as Attorney General of Holland, and later as a member of the Committee of Counsellors) was eventually asked to draft an edict to express the policy of toleration. This edict, Decretum pro pace ecclesiarum was completed in late 1613 or early 1614. The edict put into practice a view that Grotius had been developing in his writings on church and state (Erastianism): that only the basic tenets necessary for undergirding civil order (e.g., the existence of God and His providence) ought to be enforced while differences on obscure theological doctrines should be left to private conscience. The edict "imposing moderation and toleration on the ministry", was backed up by Grotius with "thirty - one pages of quotations, mainly dealing with the Five Remonstrant Articles." In response to Grotius' Ordinum Pietas, Professor Lubbertus published Responsio Ad Pietatem Hugonis Grotii in 1614, later that year Grotius anonymously published Bona Fides Sibrandi Lubberti in response to Lubbertus.

Jacobus Trigland joined Lubbertus in expressing the view that tolerance in matters of doctrine was inadmissible, denouncing Grotius' stance in his 1615 works Den Recht - gematigden Christen: Ofte vande waere Moderatie and Advys Over een Concept van moderatie.

The edict Grotius penned attempting to enforce toleration did not have the intended effect, and hostilities flared throughout the republic. As anger escalated, it appeared ever more likely that a national synod would be called. Grotius wrote emphatically that such could not take place without the consent of the civil authorities, the States of Holland, and that it was they who must appoint attendees. Grotius hoped that by preventing the church authorities from calling their own synod, an international synod would be called by the civil authorities and attending foreigners from Germany and England would have a beneficial influence on the conflict (such as Overall and Georg Lingelsheim (Counsellor to the Elector Palatine in Heidelberg) both familiar with his works).

In late 1615, when Middelburg professor Antonius Walaeus published Het Ampt der Kerckendienaren (a response to Johannes Wtenbogaert's 1610 Tractaet van 't Ampt ende authoriteit eener hoogher Christelijcke overheid in kerckelijkcke zaken) he sent Grotius a copy out of friendship. This was a work "on the relationship between ecclesiastical and secular government" from the moderate counter - remonstrant viewpoint. In early 1616 Grotius also received the 36 page letter championing a remonstrant view Dissertatio epistolica de Iure magistratus in rebus ecclesiasticis from his friend Gerardus Vossius. The letter was "a general introduction on (in)tolerance, mainly on the subject of predestination and the sacrament... [and] an extensive, detailed and generally unfavourable review of Walaeus' Ampt, stuffed with references to ancient and modern authorities." When Grotius wrote asking for some notes "he received a treasure - house of ecclesiastical history. ...offering ammunition to Grotius, who gratefully accepted it". Around this time (April 1616) Grotius went to Amsterdam as part of his official duties, trying to persuade the civil authorities there to join Holland's majority view about church politics.

In early 1617 Grotius debated the question of giving counter - remonstrants the chance to preach in the Kloosterkerk in The Hague which had been closed. During this time lawsuits where brought against the States of Holland by counter - remonstrant ministers and riots over the controversy broke out in Amsterdam.

As the conflict between civil and religious authorities escalated, in order to maintain civil order Oldenbarnevelt eventually proposed that local authorities be given the power to raise troops (the Sharp Resolution of August 4, 1617). Such a measure putatively undermined the authority of the stadtholder of the republic, Maurice of Nassau, Prince of Orange. Maurice seized the opportunity to solidify the preeminence of the Gomarists, whom he had supported, and to eliminate the nuisance he perceived in Oldenbarnevelt (the latter had previously brokered the Twelve Years' Truce with Spain in 1609 against Maurice's wishes). During this time Grotius made another attempt to address ecclesiastical politics by completing De Imperio Summarum Potestatum circa Sacra, on "the relations between the religious and secular authorities... Grotius had even cherished hopes that publication of this book would turn the tide and bring back peace to church and state". Due to events De Imperio would not be published until 1647 (two years after Grotius' death). What forestalled the publication was Maurice's ordering the arrest of Oldenbarnevelt and Grotius on 29 August 1618. Ultimately, Oldenbarnevelt was executed, and Grotius was sentenced to life imprisonment in Loevestein castle. In 1618 the Synod of Dort was held ending the Vorstius controversy by declaring him unworthy of the professorship, which was met with the approval of King James' representatives who were in attendance.

From his imprisonment in Loevestein, Grotius made a written justification of his position "as to my views on the power of the Christian [civil] authorities in ecclesiastical matters, I refer to my... booklet De Pietate Ordinum Hollandiae and especially to an unpublished book De Imperio summarum potestatum circa sacra, where I have treated the matter in more detail... I may summarize my feelings thus: that the [civil] authorities should scrutinize God's Word so thoroughly as to be certain to impose nothing which is against it; if they act in this way, they shall in good conscience have control of the public churches and public worship - but without persecuting those who err from the right way." Because this stripped Church officials of any power some of their members (such as Johannes Althusius in a letter to Lubbertus) declared Grotius' ideas diabolical.

In 1621, with the help of his wife and maidservant, Grotius managed to escape the castle in a book chest and fled to Paris. In the Netherlands today, he is mainly famous for this daring escape. Both the Rijksmuseum in Amsterdam and the museum Het Prinsenhof in Delft claim to have the original book chest in their collection.

Grotius was well received in Paris by his former acquaintances and was granted a royal pension under Louis XIII. It was there in France that Grotius completed his most famous philosophical works.

While in Paris, Grotius set about rendering into Latin prose a work which he had compiled in prison, providing rudimentary yet systematic arguments for the truth of Christianity. (Showcasing Grotius' skill as a poet, the earlier Dutch version of the work, Bewijs van den waren Godsdienst (pub. 1622), was written entirely in didactic verse.) The Latin work was first published in 1627 as De veritate religionis Christianae.

It was the first Protestant textbook in Christian apologetics, and was divided into six books. Part of the text dealt with the emerging questions of historical consciousness concerning the authorship and content of the canonical gospels. Other sections of the work addressed pagan religion, Judaism and Islam. What also distinguished this work in the history of Christian apologetics is its precursor role in anticipating the problems expressed in Eighteenth century Deism, and that Grotius represents the first of the practitioners of legal or juridical apologetics in the defence of Christian belief. Hugely popular, the book was translated from Latin into English, Arabic, Persian and Chinese by Edward Pococke for use in missionary work in the East and remained in print until the end of the nineteenth century.

Grotius also developed a particular view of the atonement of Christ known as the "Governmental" or "Moral government" theory. He theorized that Jesus' sacrificial death occurred in order for the Father to forgive while still maintaining his just rule over the universe. This idea, further developed by theologians such as John Miley, became one of the prominent views of the atonement in Methodist Arminianism.

Living in the times of the Eighty Years' War between Spain and the Netherlands and the Thirty Years' War between Catholic and Protestant European nations (Catholic France being in the otherwise Protestant camp), it is not surprising that Grotius was deeply concerned with matters of conflicts between nations and religions. His most lasting work, begun in prison and published during his exile in Paris, was a monumental effort to restrain such conflicts on the basis of a broad moral consensus. Grotius wrote:

Fully convinced...that there is a common law among nations, which is valid alike for war and in war, I have had many and weighty reasons for undertaking to write upon the subject. Throughout the Christian world I observed a lack of restraint in relation to war, such as even barbarous races should be ashamed of; I observed that men rush to arms for slight causes, or no cause at all, and that when arms have once been taken up there is no longer any respect for law, divine or human; it is as if, in accordance with a general decree, frenzy had openly been let loose for the committing of all crimes.

De jure belli ac pacis libri tres (On the Law of War and Peace: Three books) was first published in 1625, dedicated to Grotius' current patron, Louis XIII. The treatise advances a system of principles of natural law, which are held to be binding on all people and nations regardless of local custom. The work is divided into three books:

• Book I advances his conception of war and of natural justice, arguing that there are some circumstances in which war is justifiable.

• Book II identifies three 'just causes' for war: self - defense, reparation of injury, and punishment; Grotius considers a wide variety of circumstances under which these rights of war attach and when they do not.

• Book III takes up the question of what rules govern the conduct of war once it has begun; influentially, Grotius argued that all parties to war are bound by such rules, whether their cause is just or not.

The arguments of this work constitute a theory of Just War. Roughly, the second book takes up questions of jus ad bellum (justice in the resort to war) and the third, questions of jus in bello (justice in the conduct of war). The way that Grotius conceived of these matters had, together with Francisco de Vitoria's De potestate civili, a profound influence on the tradition after him and on the later formulation of international law.

Many exiled Remonstrants began to return to the Netherlands after the death of Prince Maurice in 1625 when toleration was granted them. In 1630 they were allowed complete freedom to build and run churches and schools and to live anywhere in Holland. The Remonstrants guided by Uytenbogaert set up a presbyterial organization. They established a theological seminary at Amsterdam where Grotius came to teach alongside Episcopius, Limborch, Curcellaeus, and Le Clerc.

But unlike many others, Grotius refused to ask for pardon since it would imply an admission of guilt, and was denied repatriation despite his repeated requests. Driven out once again after attempting to return to Rotterdam in October of 1631, Grotius fled to Hamburg.

In 1634 Grotius met the opportunity to serve as Sweden's ambassador to France. The recently deceased Swedish king, Gustavus Adolphus had been an admirer of Grotius (he was said to have carried a copy of De jure belli ac pacis always in his saddle when leading his troops), and his successor's regent, Axel Oxenstierna, was keen to have Grotius in his employ. Grotius accepted the offer and took up diplomatic residence at Paris, which remained his home until he was released from his post in 1645.

While departing from his last visit to Sweden, Grotius was shipwrecked on his voyage. He washed up on the shore of Rostock, ill and weather - beaten, and on August 28, 1645 he died; his body at last returned to the country of its youth, being laid to rest in the Nieuwe Kerk in Delft.

Grotius' personal motto was Ruit hora ("Time is running away"); his last words were "By understanding many things, I have accomplished nothing." Significant friends and acquaintances of his included the theologian Franciscus Junius, the poet Daniel Heinsius, the philologist Gerhard Johann Vossius, the historian Johannes Meursius, the engineer Simon Stevin, the historian Jacques Auguste de Thou, and the Arabic scholar Erpinius. He was also friend with the Flemish Jesuit Andreas Schottus.

The Peace Palace Library in The Hague holds the Grotius Collection, which has a large number of books by and about Hugo Grotius. The collection was based on a donation from Martinus Nijhoff of 55 editions of De jure belli ac pacis libri tres.