Canon of Kings

The Canon of Kings was a dated list of kings used by ancient astronomers as a convenient means to date astronomical phenomena, such as eclipses. The Canon was preserved by the astronomer Claudius Ptolemy, and is thus known sometimes as Ptolemy's Canon. It is one of the most important bases for our knowledge of ancient chronology.

The Canon derives originally from Babylonian sources. Thus, it lists Kings of Babylon from 747 BC until the conquest of Babylon by the Persians in 539 BC, and then Persian kings from 538 to 332 BC. At this point, the Canon was continued by Greek astronomers in Alexandria, and lists the Macedonian kings from 331 to 305 BC, the Ptolemies from 304 BC to 30 BC, and the Roman Emperors from 29 BC to 160 AD.

The Canon only increments by whole years. Thus, monarchs who reigned for less than one year are not listed, and only one monarch is listed in any year with multiple monarchs. Usually, the overlapping year is assigned to the monarch who died in that year, but not always. Note that both periods where no king is listed represent times when Sennacherib, King of Assyria, had effective control over Babylon. His name is not listed because of the antipathy the Babylonians had for him due to his destruction of the city in 689 BC.