Hugo Grotius (Huig de Groot, or Hugo de Groot; Delft, 10 April 1583 – Rostock, 28 August 1645) worked as a jurist in the Dutch Republic and laid the foundations for international law, based on natural law. He was also a philosopher, Christian apologist, playwright, and poet.

Early life
The Dutch were at war with Spain and Portugal when the loaded merchant ship, the Santa Catarina, had been captured by captain Jacob van Heemskerk 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 the force, many of the 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 were demanding their cargo back. The scandal led to a public judicial hearing and a wider contest to sway public (and international) opinion. It was in this wider contest that representatives of the Company called upon Grotius to draft a polemical defense 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 Mare Liberum (The Free Seas, 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', 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 sovereignty over the waters around the British Isles. 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 later 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).

De Indis and Mare Liberum
Background Protestantism Reformation Calvinist-Arminian Debate
People Jacobus Arminius Hugo Grotius The Remonstrants John Wesley Doctrine Total depravity Prevenient grace Substitutionary atonement Unlimited atonement Conditional election 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.
The edict did not have the intended effect, and hostilities flared throughout the republic. To maintain civil order, Oldenbarnevelt eventually proposed that local authorities be given the power to raise troops (the Sharp Resolution). Such a measure putatively undermined the authority of the stadtholder of the republic, Maurice of Nassau, Prince of Orange, son of William the Silent. Maurice seized the opportunity to solidify the preeminence of the Gomarists, whom he had supported, and to eliminate the nuissance he perceived in Oldenbarnevelt (the latter had previously brokered the Twelve Years' Truce with Spain in 1609 against Maurice's wishes). He had Oldenbarnevelt and Grotius arrested on 29 August 1618. Ultimately, Oldenbarnevelt was executed, and Grotius was sentenced to life imprisonment in Loevestein castle.
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 here in France that Grotius completed his most famous philosophical works.

The Arminian controversy, arrest and exile
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 the dominant view in Arminianism and Methodism.

On The Truth of the Christian Religion
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, 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:
De jure belli ac pacis libri tres (On the Laws of War and Peace) 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:
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 a profound influence on the tradition after him and on the later formulation of international law.

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. Later years
The section could be improved by integrating relevant items into the main text and removing inappropriate items.
Grotius hic Hugo est, Batavum captivus et exsul
Legatus regni, Suecia magna, tui.
(Here is Hugo Grotius, Batavian captive and exile
Ambassador of thy realm, great Sweden!)

Grotius' personal motto: Ruit hora. (Time is running away.)
Grotius' last words: "By understanding many things, I have accomplished nothing."
Grotius' self-composed epitaph:
Significant friends and acquaintances:

• Franciscus Junius - theologian
  Daniel Heinsius - poet, dramatist
  Gerhard Johann Vossius - philologist, theologian
  Johannes Meursius - classical historian
  Simon Stevin - engineer, scientist
  Jacques Auguste de Thou - historian
  Thomas Erpinius - Arabic scholar
  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.
  The American Society of International Law has been holding an annual series of Grotius Lectures since 1999. Trivia
  Works are listed in order of publication, with the exception of works published posthumously or after long delay (estimated composition dates are given). Where an English translation is available, the most recently published translation is listed beneath the title.
  Commentary on the Law of Prize and Booty, ed. Martine Julia van Ittersum (Liberty Fund, 2006).
  The Free Sea, ed. David Armitage (Liberty Fund, 2004).
  The Antiquity of the Batavian Republic, ed. Jan Waszink (van Gorcum, 2000).
  Meletius, ed. G.H.M. Posthumus Meyjes (Brill, 1988).
  The Annals and History of the Low-Countrey-warrs, ed. Thomas Manley (London, 1665).
  Ordinum Hollandiae ac Westfrisiae pietas, ed. Edwin Rabbie (Brill, 1995).
  De imperio summarum potestatum circa sacra, ed. Harm-Jan van Dam (Brill, 2001).
  Defensio fidei catholicae de satisfactione Christi, ed. Edwin Rabbie (van Gorcum, 1990).
  The Jurisprudence of Holland, ed. R.W. Lee (Oxford, 1926).
  The Rights of War and Peace, ed. Richard Tuck (Liberty Fund, 2005).
  The Truth of the Christian Religion, ed. John Clarke (Edinburgh, 1819).
  
  Adamus exul (The Exile of Adam; tragedy) - The Hague, 1601
  De republica emendanda (To Improve the Dutch Republic; manuscript 1601) - pub. The Hague, 1984
  Parallelon rerumpublicarum (Comparison of Constitutions; manuscript 1601-02) - pub. Haarlem 1801-03
  De Indis (On the Indies; manuscript 1604-05) - pub. 1868 as De Jure Praedae
  Christus patiens (The Passion of Christ; tragedy) - Leiden, 1608
  Mare Liberum (The Free Seas; from chapter 12 of De Indis) - Leiden, 1609
  De antiquitate reipublicae Batavicae (On the Antiquity of the Batavian Republic) - Leiden, 1610
  Meletius (manuscript 1611) - pub. Leiden, 1988
  Annales et Historiae de rebus Belgicus (Annals and History of the Low Countries; manuscript 1612) - pub. Amsterdam, 1657
  Ordinum Hollandiae ac Westfrisiae pietas (The Piety of the States of Holland and Westfriesland) - Leiden, 1613
  De imperio summarum potestatum circa sacra (On the power of sovereigns concerning religious affairs; manuscript 1614-17) - pub. Paris, 1647
  De satisfactione Christi adversus Faustum Socinum (On the satisfaction of Christ against [the doctrines of] Faustus Socinus) - Leiden, 1617
  Inleydinge tot de Hollantsche rechtsgeleertheit (Introduction to Dutch Jurisprudence; written in Loevenstein) - pub. The Hague, 1631
  Bewijs van den waaren godsdienst (Proof of the True Religion; didactic poem) - Rotterdam, 1622
  Apologeticus (Defense of the actions which led to his arrest) - Paris, 1922
  De jure belli ac pacis (On the Laws of War and Peace) - Paris, 1625 (2nd ed. Amsterdam 1631)
  De veritate religionis Christianae (On the Truth of the Christian religion) - Paris, 1627
  Sophompaneas (Joseph; tragedy) - Amsterdam, 1635
  De origine gentium Americanarum dissertatio (Dissertation of the origin of the American peoples) - Paris 1642
  Via ad pacem ecclesiasticam (The way to religious peace) - Paris, 1642
  Annotationes in Vetus Testamentum (Commentaries on the Old Testament) - Amsterdam, 1644
  Annotationes in Novum Testamentum (Commentaries on the New Testament) - Amsterdam and Paris, 1641-50
  De fato (On Destiny) - Paris, 1648 Selected works
  
  Eighty Years' War
  History of the Netherlands
  Synod of Dordrecht
  Just war
  Natural law
  International waters
  Freedom of the seas
  English school of international relations theory (Grotian School) Notes
  
  Craig, William Lane. The Historical Argument for the Resurrection of Christ During the Deist Controversy, Texts and Studies in Religion Volume 23. Edwin Mellen Press, Lewiston, New York & Queenston, Ontario, 1985.
  Dulles, Avery. A History of Apologetics. Eugene, Oregon: Wipf & Stock, 1999.
  Dumbauld, Edward. The Life and Legal Writings of Hugo Grotius. Norman, OK: University of Oklahoma Press, 1969.
  Edwards, Charles S. Hugo Grotius: The Miracle of Holland. Chicago: Nelson Hall, 1981.
  Grotiana. Assen, The Netherlands: Royal Van Gorcum Publishers. (journal of Grotius studies, 1980-)
  Haakonssen, Knud. Grotius and the History of Political Thought, Political Theory, vol. 13, no. 2 (May, 1985), 239-265.
  Haggenmacher, Peter. Grotius et la doctrine de la guerre juste. Paris: Presses Universitaires de France, 1983.
  Hugo Grotius, Theologian. ed. Nellen and Rabbie. New York: E.J. Brill, 1994.
  Hugo Grotius and International Relations. ed. Bull, Kingsbury and Roberts. New York: Clarendon Press, 1990.
  Ittersum, Martine Julia van. Hugo Grotius, Natural Rights Theories and the Rise of Dutch Power in the East Indies 1595-1615. Boston: Brill, 2006.
  Knight, W.S.M. The Life and Works of Hugo Grotius. London: Sweet & Maxwell, Ltd., 1925.
  Lauterpacht, Hersch. The Grotian Tradition in International Law, British Yearbook of International Law, 1946.
  Tuck, Richard. Philosophy and Government: 1572-1651. New York: Cambridge, 1993.
  Tuck, Richard. The Rights of War and Peace: Political Thought and the International Order from Grotius to Kant. New York: Oxford, 1999.
  Vollenhoven, Cornelius van. Grotius and Geneva, Bibliotheca Visseriana, vol. vi, 1926.
  Vollenhoven, Cornelius van. Three Stages in the Evolution of International Law. The Hague: Nijhoff, 1919.
  Vreeland, Hamilton. Hugo Grotius: The Father of the Modern Science of International Law. New York: Oxford University Press, 1917.