David Pacifico (1784 – April 12, 1854) was of PortugueseJewish descent. He was born a British subject at Gibraltar 1784 and died in London April 12, 1854. He is best known to history as "Don Pacifico".
In 1850, Don Pacifico was the key figure in the international crisis known as the Don Pacifico Affair. In 1847, while he was living and working in the Greek capital, Athens, as the Portuguese consul, Don Pacifico's home was attacked and vandalised by an anti-Semitic mob that included the sons of a government minister, whilst police looked on and did nothing. Don Pacifico appealed to the Greek government for compensation for loss of possessions, including documents relating to a substantial claim against the Portuguese government for monies owed. When in 1848 it became clear that compensation would not be given, he appealed to the British.
Because Don Pacifico was born in Gibraltar and was therefore a British subject, then foreign minister Lord Palmerston decided on military action and dispatched a squadron of the Royal Navy to blockade Piraeus, the port of Athens. After some eight weeks of blockade, the Greek government at last paid suitable compensation to Pacifico. When challenged in Parliament on this issue, Palmerston justified his actions with, "Civis romanus sum": translated as "I am a Roman citizen", this declaration by a Roman would protect him from harm anywhere in the ancient Roman empire.