Piracy exists since the first mariners sailed the seas, as it was a way to look for economic benefits for the people living at the coasts, generally poor. At the beginning it was not a condemned activity, if it was not done to fellow citizens. It was actually licit, and even praised, when the victim was a foreign. Homer wrote in his works about the adventures of Achilles and Menelaus, who did not hesitate to do lucrative pillages in enemy territoty, and Ulysses, who established his hide-out in the island of Itaca.
The Ancient Mediterranean
After the disappearing of the Minoian civilization, there is not a clear ruler of the Mediterranean anymore. Since the city-states start to arise, this sea becomes a busy trade route, and unsafe at the same time. Etrurian and Thracian pirates attack periodically the Greek and southern Italian coasts. Phoenicians associate the concepts of piracy and trade, and feed their slave trade this way. The island of Crete becomes the greatest pirate nest in the Mediterranean. It was not until the VI century BC that Athens carried out the first campaign against the pirates in order to have peace for its trade routes. At that time, the fact of being a pirate starts to be disapproved, as this activity looks for an individual benefit instead that for the community.
Rome had serious problems with Cilician pirates, who assaulted Sicily and reached as far as Ostia. It even seems that Julius Caesar himself was kidnapped by the pirates when he was young (although immediately afterwards he looked for help, reached them and made them crucify). In the I century BC, Pompeius conquers Cilicy, and offers the pirates a smart choice: to join the Roman navy, or to be enslaved. During centuries, the "Mare Nostrum" was a safe place for Romand transport and trade, not being so though in the Atlantic coasts.
After Rome, Byzantium became the greatest Mediterranean power, but as it did not control the whole of the coasts, it had to face continuous attacks from Narentine, Cilician and North African pirates. In 1204 Constantinople is taken by the crusaders, who start making piracy activities in the Eastern coastlines and establish a lucrative trade of Arab and Turkish slaves. Genovese and Venetian trade routes were also watched and assaulted by Catalonians, Sicilians and Maltese. At this time appears the expression "far il corso", literally make his own way, used by mariners that join pirate vessels to leave their poverty situation. From there came the latin word "corsario", for "privateer".
In the North Sea, the seasons of Spring and Autumn, with its dense fogs, were an ideal place for piracy. First Vikings in the coastlines, and then Bretons, Irish and Bordolese in the trade routes of English, Dutch and Baltic ships. In the XIV century the Hansa appears, as a trade association between septentrional cities, with the aim of offering mutual protection. However the agreements were rarely accomplished, and while every lord had pirates at his service for acting against other cities.
Golden Age and decadence
From the XVI century, the piracy becomes a politic matter. Great States start to influence in it, by financing pirate vessels or signing anti-piracy agreements with other States. As a consequence of this influence, the new privateers have more modern and sofisticated ships, giving place to a true Golden Age of piracy. Most important were port cities of Argelia (Bejaia, Oran, Algiers), that were protected and financed by Muslim kingdoms, specially the Ottoman and the nasri of Granada, by using these privateers to weaken the influence of Christian kingdoms. It is the time of the Barbarossa brothers (Baba Aruj and Khaid ar Din) who, associeted to the Ottoman Empire, caused great losses to the Spanish fleet.
From the XVII century, the troubles caused by privateers to their own protectors make these retire progressively their support. At the XVIII century the fleets of England, France and the United Provinces were powerful enough to control the decadent pirate activity, that disappeared one century later.