In Mare Liberum (The Free Seas, published 1609) Hugo 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.