So Where Did The Pirates Come From?

Piracy has been a persistent problem for thousands of years, in fact from the time ships started to sail the oceans. The phenomenon was not limited to a particular region and contemporary universal condemnation of piracy might suggest that it was always viewed with disdain. However, pirates were repeatedly tolerated and sometimes even viewed by states as a certain foreign policy tool to be employed for their own interests.
In addition to "pirates" who attacked any ships indifferent of the flag of State it was flying, or committed robbery or other acts of violence at sea against any persons or ships for private ends whether in time of war or peace, there were "privateers", "buccaneers", "filibusters", "corsairs", "freebooters", all having their own definitions. There is no room in this contribution to elaborate extensively on all the definitions but some of the main features of "privateering" will be noted as it is the most wide spread and encompassing phenomenon.
A 'privateer' was a person under a contract to a government, usually in the form of a 'letter of marque' (sometimes having the full title 'a letter of marque and reprisal') issued by a recognized State authorizing him to attack and capture vessels having nationality of a State which the former State was at war with. The contract most often also provided that the government received a share of the profits. The most obvious difference between the pirates and the privateers was that in the event of capture, the latter were subject to the rules and laws of war and were to be treated the same as prisoners of war. Privateers were hence supposed to follow rules of naval warfare, including limiting their activities to times of declared war, precluding attacks on the vessels of cargoes of neutral States and their nationals, and submitting to procedures of prize law.
Privateering became an accepted part of the law of naval warfare authorized at times by all significant naval powers. however, there were many instances when a particular person was crossing the line and moving from being a pirate to a privateer and vice versa. Because of this confusing system, there were differences in treatment of sea outlaws. this fluctuated almost till the middle of the nineteenth century, when the Declaration Respecting Maritime Law (the Paris Declaration) abolishing privateering was signed in 1856 by most of the European imperial powers.
Spain and the United States stayed away from the Paris Declaration and interestingly, the Constitution of the United States still contains provisions which gives to the Congress power to grant letters of marque and reprisal.
It was until the 20th century that the attempts to establish common definition of piracy (different from privateering) became more persistent. in the 1920's, the Assembly of the League of Nations requested the Council of the League of Nations to prepare a provisional list of subjects of international law which would seem to be the most desirable and realizable. The committee responsible for drawing up this list included piracy and also enclosed Draft Provision for the Suppression of Piracy, but the subject was later dropped by the Council, reportedly on grounds that piracy was no longer a pressing issue to the international community and that the achievement of a universal agreement seemed somewhat difficult.
Nevertheless, in the 1930's, the so-called Harvard Research Group had already drafted a Convention on Piracy, commonly known as the 'Harvard Draft'. The International Law Commission during its preparatory work on the theme of the Law of the Sea drew substantially from the Harvard Draft provisions as the basis for the piracy articles of what later became the Convention on the High Seas (1958).
That definition of piracy in Article 15 of the HSC together with the relevant provisions on piracy in Articles 14 and 16-21 were mostly incorporated into the United Nations Convention on the Law Of the Sea (UNCLOS) as the primary multilateral instrument in the field of international law. Therefore, the UNCLOS definition of piracy comprises four main elements:

1. illegal act of violence, detention or depredation
2. private ends
3. involvement of two ships (the possibility of involvement of aircraft falls beyond the scope of the present contribution, although theoretically it cannot be instantly denied that an act of piracy could involve not only two aircraft but also aircraft and a ship); and
4. location at the high seas.