De Indis and Mare Liberum
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).
Read more about this topic: Hugo Grotius