Hugo Grotius

As you read this introduction to Grotius and his work, think about how his ideas may have shaped the arguments you saw in the previous unit. Focus on the sections on Natural Law and the Doctrine of Just War.

Portrait of Hugo Grotius by Michiel Jansz van Mierevelt, 1631

Hugo Grotius by Michiel Jansz van Mierevelt, 1631

Hugo Grotius 
(Huig de Groot, or Hugo de Groot) (April 10, 1583 – August 28, 1645) worked as a jurist in the Dutch Republic and laid the foundations for international law, based on natural law. He was also a theologian, philosopher, statesman, Christian apologist, playwright, and poet. His masterwork, De lure Belli ac Pacis (On the Law (and Rights and Wrongs) of War and Peace, 1625) secured his reputation as the founder of the theory of natural law.

Grotius removed natural law from the jurisdiction of moral theologians and made it the business of lawyers and philosophers, by asserting that by their very nature, natural laws were authoritative in themselves, with or without faith in God. He held that the moral ethics of natural law applied to all social and rational beings, Christian and non-Christian alike. Grotius also promoted the concept of Just War as war which was required by natural, national and divine law under certain circumstances. He developed a series of rules for right conduct of war, based on the principle that actions in a war should serve the right. Grotius also wrote De Jure Praedae (On the Law of Prize and Booty), one chapter of which, defending free access to the ocean for all nations, was reprinted and widely circulated under the title Mare Liberum.


Grotius was born on Easter Sunday, April 10, 1583, in Delft, Holland, to a moderately prosperous and well-educated family. His father had been burgomaster of Delft and curator of Leiden University. Grotius showed exceptional talent as a child; when he was eight, he began writing skillful elegies in Latin and soon became the best pupil of the famous Latinist Joseph Scaliger. At eleven, he was a student in the Faculty of Letters at the University of Leiden. His father entrusted him to a preacher and theologian from The Hague, Johan van Oldenbarnevelt, a leading Dutch politician, and in 1598, when he was only 15, Grotius accompanied him on an embassy to the royal court of France. King Henry IV was impressed by his unusual intelligence and called him “the miracle of Holland.”

Grotius remained in France and studied law at Orléans, and the same year produced Pontifex Romanus, six monologues offering a synthesis of the political situation in 1598. In 1599 he returned to The Hague to begin a law career and lodged for a time with his former teacher, Uyttenbogaert. In 1600 he wrote Mirabilia, a poem about the events on land and sea in the first half of that year.

In 1601 the states of Holland decided to emphasize their autonomy from Spain and made Grotius their official Latin historiographer, commissioning him to write a description of the Dutch revolt against Spain. Grotius entitled this work Annales et Historiae de Rebus Belgicis in emulation of the Roman historian Tacitus. It had two parts, the Annales, covering the period from 1559 to 1588, and the Historiae beginning in 1588 and concluding with the Twelve Years' Truce (1609–1621).

On his return to The Hague, Grotius opened a law practice, and his clients included the Dutch East India Company, Oldenbarnevelt, and Prince Maurice of Nassau. Holland was then at peace with Spain and Portugal, but in 1604 a Dutch admiral seized the Portuguese ship Santa Catarina. The Dutch East India Company asked Grotius to write a treatise, De Jure Praedae (On the Law of Prize and Booty), contending that the Dutch were justified in seizing the ship because Spain and Portugal had deprived them of the trading rights. One chapter of this treatise, defending free access to the ocean for all nations, was reprinted and widely circulated under the title Mare Liberum.

In 1607, when the position of attorney general (advocaat fiscaal) of Holland, Zeeland and West Friesland became available, Prince Maurice of Nassau chose Grotius over two other older and more experienced candidates.

In 1609 he married Maria van Reigersberch, the daughter of the burgomaster of Veere, a courageous woman who supported him faithfully during difficult times. They had three daughters and four sons. That same year Grotius published a drama, Christus Patiens, that was to be widely imitated. In 1613 Grotius was appointed pensionary (governor) of Rotterdam, and led a delegation to England to protest the seizure of the cargoes of two Dutch ships on the seas near Greenland.

A political dispute arose in Holland between orthodox Calvinists and reformers over Arminianism. Grotius, Oldenbarnevelt and other supporters of religious tolerance sided with the reformers or Remonstrants against Maurice, the Calvinist establishment and other Contra-Remonstrants. On August 29, 1618, Maurice and his allies carried out a coup d'état, overthrowing the States General (of which Grotius was a member in his position as pensionary of Rotterdam) and imprisoning him along with Oldenbarnevelt and Rombout Hoogerbeets, the pensionary of Leiden.

In a purge of remonstrants from the government, Oldenbarnevelt was executed, and Grotius and Hoogerbeets were sentenced to life imprisonment. Grotius had access to books and writing materials in prison, and was permitted to correspond with outsiders, but there was constant danger that the authorities might also decide to execute him. In 1621, with the help of his wife Maria, Grotius escaped by hiding himself in a large trunk which she sent to him, and having it carried out of the prison, pretending that it contained a large number of books. He fled to Antwerp and then to Paris, where his family joined him.

Life in Paris

The French authorities welcomed Grotius and awarded him an annual pension. In 1625, a Parisian press published his masterpiece De Jure Belli ac Pacis (On the Law of War and Peace), in which he laid the foundations of international law. The work quickly made him famous, and in 1631 he attempted to return to the Netherlands. Prince Maurice had died in 1625, and Prince Frederick Henry of Orange intervened on his behalf, but Grotius was still threatened with arrest by the government. He was offered the governor generalship of the Dutch East India Company in Asia, but the authorities moved against him, offering a large reward for his capture and forcing him to flee Holland in April 1632, never to return.

Grotius had achieved such a reputation internationally that in 1634, the Swedish chancellor, Count A. G. Oxenstierna, offered him the position of Swedish ambassador in Paris. Grotius accepted and wrote a drama in honor of the count, Sophompaneas (1635), relating the fortunes of the biblical Joseph as minister at the Egyptian court. The great Dutch poet Joost van den Vondel translated this drama as Joseph in't Hof (Joseph at the Court).

Grotius served, with mixed success, for ten years as ambassador for Sweden, which was then a major European political power. He helped negotiate a treaty which eventually ended the Thirty Years' War, but at one point he made a misstep which required the Swedish chancellor to come to Paris and intervene personally.

During this time, Grotius became increasingly concerned with the task of achieving Christian unity among the various Protestant factions and the Catholics. Intellectually, the effort to unite Christianity raised many philosophical and theological questions, and politically Grotius was in a position to exert influence in Europe. He wrote some interesting works on theology, many of which were collected in his Opera Omnia Theologica.

From 1636–1637 Grotius worked on the Historia Gothorum, Vandalorum et Langobardom (History of the Goths, Vandals, and Lombards), and edited the works of Tacitus (1640). After Queen Christina ascended the Swedish throne in 1644, she began to dismantle the political structure of her rival Oxenstierna. She relieved Grotius of his ambassadorship and called him to Stockholm to assume a different position.

Reluctantly, he set sail in March of 1645. His ship was wrecked in the Baltic and he barely escaped with his life. After a few months in Sweden, though he was received there with great honor, he decided to return to Germany. Weather conditions were poor; the normally short journey took eight days and Grotius died of exhaustion two days later in Rostock, Germany, on August 28, 1645. His last words are said to have been, "By attempting many things, I have accomplished nothing."

Thought and Works

Grotius was a philosopher, a legal scholar, a theologian, a poet, a dramatist, a philologist and a prolific writer and editor. It is said that he later regretted that he had chosen a career in law instead of in literature. He never stopped writing, even while carrying out the legal, political and administrative responsibilities to which he had been appointed.

As a poet and philologist, Grotius edited, with a commentary, Martianus Capella's handbook of the seven liberal arts (1598), the Phaenomena, a work on astronomy by the third century B.C.E. Greek Aratus of Soli; he also collaborated with the humanist Daniel Heinsius on a Latin translation of the Greek bucolic poet Theocritus. In 1601 he published Sacra, a volume of Latin poetry made up of sacred poems, together with the drama Adamus Exul (Adam in Exile). The drama was widely read and imitated, and was admired by the English poet John Milton. In 1614 he again edited a Roman author, Lucanus.

He defended his position in the Dutch religious conflict in Apologeticus eorum qui Hollandiae Westfrisiaeque et vicinis quibusdam nationibus ex legibus praefuerunt. He also worked on a Latin translation of Euripides' Phoenissae (1630) and on a commentary on the Bible, Annotationes in Libros Evangeliorum.

Two of his philosophical works were of major significance in Europe, De Jure Belli ac Pacis (On the Law of War and Peace, 1625), and De iure praedae commentarius (Commentary on the Law of Prize and Booty, 1604). The sole manuscript of Commentary on the Law of Prize and Booty was discovered in a trunk when some of Grotius’ descendants sold a collection of his papers in 1864. It discussed the legal question of whether a private agent such as the Dutch East India Company had the right to employ force against another private agent which was restricting its actions. The treatise was also intended to glorify Holland and the Dutch East India Company while defaming Spain and Portugal. Only the twelfth chapter had been published by Grotius, as Mare Liberum (On the Freedom of the Seas), and had aroused considerable interest in Europe.

Grotius’ reputation as a philosopher is based on De Jure Belli ac Pacis (On the Law of War and Peace), part of which was written during his imprisonment. It consists of an introduction and three books, more than nine hundred pages in translation. In the introduction, or Prolegomena, Grotius articulates the philosophical foundations for the rest of the work. Book One defines the concept of just war, argues for the legitimacy of war, and identifies who may legitimately wage war. Book Two examines the causes of war, origins of property, the transfer of legal rights and other such issues. Book Three defines the rightful conduct of belligerents in war. After the initial publication in 1625, Grotius printed several more editions, adding more references without substantially changing the arguments.

Natural Law

Discussion of natural law had begun in the ancient world; Thomas Aquinas was the first to formulate a complete theory of natural law. Some scholars refer to Grotius as the father of natural law. In the Prolegomena to De Jure Belli ac Pacis he declares that the fundamental principles of ethics, politics and law are functions of the essence of human nature. If an action agrees with the rational and social aspects of human nature, it is allowable; if it does not, it cannot be allowed. Later, in the second chapter, he proposes that God, by an act of volition, determines the meaning, or content of concepts like justice and goodness, a theory called voluntarism.

Man could learn what those fundamental natural principles are by studying human nature. A study of human nature revealed that it consists of two basic needs, or desires: the need for self-preservation and the need for society. These two needs counteracted and informed each other, the desire for self-preservation being limited by the social impulse and conversely, the desire for society being limited by the need for self-preservation. The desire for self-preservation and the need for society were both emotive and cognitive, irrational and rational, instinctive and deliberate. In order to satisfy these two needs and live successfully, man ought to do two things: abstain from what belongs to others, and engage in reasonable pursuit of what genuinely serves his interests. Grotius made these the first two elements of natural law the basis of the first four laws in De Jure Belli ac Pacis. In addition to these, from the observation of human nature Grotius derived an additional 22 fundamental laws, such as, “Evil deeds must be corrected" and, "Good deeds must be recompensed."

Why should human beings obey laws? Grotius, borrowing from Francisco Suárez, maintained that natural law obliges us to perform actions which contribute to our rationality, sociability and need for self-preservation. For example, evil deeds must be corrected because they have unjustly benefited some while unjustly harming others, thus disturbing the moral equilibrium of society. In order to maintain healthy social relations, it is imperative that evil deeds be punished.

During that period, European expansionism was beginning to impinge on the liberty of indigenous peoples in the Americas, Africa and Asia. Grotius did not agree with those who wanted to exclude non-Christians from the jurisdiction of natural law. Natural law, according to him, applied to all rational and social beings.

Doctrine of Just War

Grotius regarded war as an instrument of right, rather than a condition outside of the realm of morality and law. He argued that war was not only compatible by was sometimes required by all three forms of law, the law of nature, law of nations (international law) and divine law, saying, "where judicial settlement fails, war begins" (De Jure Belli ac Pacis. II.1.2.1):

He who wills the attainment of a given end, wills also the things that are necessary to that end. God wills that we should protect ourselves, retain our hold on the necessities of life, obtain that which is our due, punish transgressors, and at the same time defend the state… But these divine objectives sometimes constitute causes for undertaking and carrying on war… Thus it is God's Will that certain wars should be waged… Yet no one will deny that whatsoever God will, is just. Therefore, some wars are just. (De iure praedae commentarius, chap. 3)

Grotius said that wars could be justly undertaken in response either to "wrongs not yet committed, or to wrongs already done" (De Jure Belli ac Pacis. II.1.2.1). He compiled a long list of wrongs which might justify war, but he also suggested limits, some of which were controversial. Even if a war were undertaken for just causes, it must be fought rightly in order to be a Just War. Grotius established three rules to govern the conduct of a war. The first was, "In war things which are necessary to attain the end in view are permissible" (De Jure Belli ac Pacis.III.1.2). He qualified this by making the criteria which made an action necessary quite restrictive. After establishing the three basic laws, Grotius set out to determine the legal and moral status of a large number of actions that might be undertaken by belligerents and to consider whether or not they would be permissible during a war. The ultimate criterion was that war was only justifiable when it serves right.

On the Truth of the Christian Religion

Grotius wrote a book defending Christianity, called De veritate religionis Christianae (On The Truth of the Christian Religion, 1632), which 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. It was the first Protestant textbook of Christian apologetics, and was divided into six books. The work discussed the emerging questions of historical consciousness concerning the authorship and content of the canonical gospels, pagan religion, Judaism and Islam, and anticipated the problems of eighteenth-century Deism. Grotius represents the first of the practitioners of legal, or juridical, apologetics in the defense of Christian belief.

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 the dominant view in Arminianism and Methodism.

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

The American Society of International Law has been holding an annual series of Grotius Lectures since 1999.


De Jure Belli ac Pacis influenced both philosophers and men of action. The Swedish King Gustavus Adolphus is said to have kept a copy of the it under his pillow, next to the Bible. Grotius’ greatest impact was on other scholars. Pierre Bayle called him "one of the greatest men in Europe." Gottfried Leibniz hailed "the incomparable Hugo Grotius." Thomas Reid spoke of "the immortal Hugo Grotius," Francis Hutcheson drew on him extensively, and David Hume cited an argument of his about the origins of property in the third appendix of his second Enquiry. His critics included Jean-Jacques Rousseau, Voltaire and the natural law theorist Samuel Pufendorf.

Early modern moral philosophy was dominated by the ethics of natural law. Grotius remained the major natural law theorist until he was displaced by Immanuel Kant’s moral philosophy and rewriting of the history of ethics. He removed natural law from the jurisdiction of moral theologians and made it the business of lawyers and philosophers. While Grotius recognized divine will in natural law, his theory asserted that by their very nature, natural laws were authoritative in themselves, with or without faith in God. He also compiled and systematized the practices of just war around principles based on natural law.

In politics, Grotius gave rise to a theory of statehood and the relations among states, which conceived of states as existing in an international society governed by a system of norms that were authoritative in themselves, and not dependent on the action of a legislature or legislator. At the same time, his theory recognized that individual states would engage in the pursuit of their own perceived interests, regardless of whether such pursuits place them in conflict with the natural law, allowing for the negotiation of a middle way.


  • De republica emendanda (To improve the Dutch republic) - 1601
  • Parallelon rerumpublicarum (Comparison of constitutions) - 1602
  • De iure praedae (On the right of capture), including Mare liberum (The Free Seas) - 1604
  • De antiquitate reipublicae Batavicae (The antiquity of Dutch republic) - 1610
  • Ordinum pietas (The piety of the States) - 1613
  • Defensio fidei catholicae de satisfactione (Defense of the Christian faith) - 1617
  • De iure belli ac pacis (On the laws of war and peace) - 1625
  • De veritate religionis Christianae (On the truth of the Christian religion) - 1627
  • Inleydinge tot de Hollantsche rechtsgeleertheit (Introduction to Dutch law) - 1631
  • Via ad pacem ecclesiasticam (The way to religious peace) - 1642
  • De imperio summarum potestatum circa sacra (On the power of sovereigns concerning religious affairs) - 1647
  • De fato (On destiny) - 1648
  • Annales et historiae de rebus Belgicis (Annals and history of the Netherlands) - 1657

Source: New World Encyclopedia,
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Last modified: Monday, September 20, 2021, 12:32 PM