David Pacifico (1784 – 12 April, 1854) was a British subject from Gibraltar of PortugueseJewish descent. He was born in 1784 and died in London 12 April, 1854. He is best known to history as "Don Pacifico" and for his role as the key figure in the Don Pacifico Affair of 1850.
In 1847, while he was living and working in the Greek capital, Athens, as the Portuguese diplomatic 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 military action would be justified and dispatched a squadron of the Royal Navy to blockade Piraeus, the port of Athens. After an eight week blockade, the Greek government paid compensation to Pacifico. When challenged in the British Parliament[by whom?] about his course of action, Lord Palmerston justified it using the phrase, "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.