The Pacifico Incident concerned a Portuguese Jew, named David Pacifico (known as Don Pacifico), who was a trader in Athens during the reign of King Otto. Pacifico had been born in Gibraltar - a British possession - and was therefore technically a British subject. In April 1847 his business was attacked and vandalised by an mob angered because they thought he was responsible for banning the "burning of Judas" - an Easter custom. Pacifico filed a claim of 888,736.57 drachmas with the Greek government for compensation for his injury which was not paid as it was deemed outrageously excessive. When he saw it was not forthcoming, he appealed in 1848 to the British government.
Liberal British Foreign Minister Palmerston, a philhellene and supporter of the Greek War of Independence 1821-1829, sent a Royal Navy squadron into the Aegean Sea on January 3, 1850 to seize Greek ships and property equal to the value of Don Pacifico's claims. The squadron eventually blockaded the port of Piraeus, the main port of the capital, Athens.
Since Greece was a state under the joint protection of three powers, Russia and France protested against its coercion by the British fleet, and the French ambassador temporarily left London, which promptly led to the termination of the affair on April 15, 1850. The claim of Don Pacifico was eventually put to arbitration and a sum of 3,750 drachmas was awarded.
The issue was taken up in the British Parliament with considerable heat. After a memorable debate (June 17), Palmerston's policy was condemned by a vote of the House of Lords. The House of Commons was moved by Roebuck to reverse the sentence, which it did (June 29) by a majority of 46. Palmerston delivered a famous speech in which he sought to vindicate, not only his claims on the Greek government for Don Pacifico, but his entire administration of foreign affairs. "As the Roman, in days of old, held himself free from indignity, when he could say, Civis Romanus sum [I am a Roman citizen], so also a British subject, in whatever land he may be, shall feel confident that the watchful eye and the strong arm of England will protect him from injustice and wrong."
This principle, of military intervention (or Gunboat Diplomacy) to protect the rights of British subjects became a defining characteristic of Victorian foreign policy and was followed by both Liberal and Conservative governments. It has since become a controversial and often maligned action and Don Pacifico is sometimes used as a watchword for inappropriate military intervention against a sovereign nation.