On This Day: September 2nd

Pharaoh Cleopatra VII of Egypt declares her son co-ruler as Ptolemy XV Caesarion.

Great Britain, along with its overseas possessions, adopts the Gregorian calendar.

The Italian city of Castro is completely destroyed by the forces of Pope Innocent X, ending the Wars of Castro.

Cicero launches the first of his Philippicae (oratorical attacks) on Mark Antony. He will make 14 of them over the following months.

Final War of the Roman Republic: Battle of Actium: Off the western coast of Greece, forces of Octavian defeat troops under Mark Antony and Cleopatra.

The United States Department of the Treasury is founded.

The Great Fire of London breaks out and burns for three days, destroying 10,000 buildings, including Old St Paul's Cathedral.

4th Spanish Armada makes landfall in Ireland at Kinsale.

Entry of Mary, Queen of Scots into Edinburgh, a spectacular civic celebration for the Queen of Scotland, marred by religious controversy.

The Treaty of Jaffa is signed between Richard I of England and Saladin, leading to the end of the Third Crusade.