Sosigenes () (

fl. ''Floruit'' ( ; usually abbreviated fl. or occasionally flor.; from Latin for 'flourished') denotes a date or period during which a person was known to have been alive or active. In English, the unabbreviated word may also be used as a noun indic ...

1st century BC The 1st century Before Christ, BC, also known as the last century BC and the last century Common Era , BCE, started on the first day of 100 BC, 100 BC and ended on the last day of 1 BC, 1 BC. The Anno Domini, AD/BC notation does not ...

) was an Ancient Greek astronomer. According to

Pliny the Elder Gaius Plinius Secundus (AD 23/24 79), known in English as Pliny the Elder ( ), was a Roman Empire, Roman author, Natural history, naturalist, and naval and army commander of the early Roman Empire, and a friend of the Roman emperor, emperor Vesp ...

's ''

Natural History Natural history is a domain of inquiry involving organisms, including animals, fungi, and plants, in their natural environment, leaning more towards observational than experimental methods of study. A person who studies natural history is cal ...

'' 18.210–212,

Julius Caesar Gaius Julius Caesar (12 or 13 July 100 BC – 15 March 44 BC) was a Roman general and statesman. A member of the First Triumvirate, Caesar led the Roman armies in the Gallic Wars before defeating his political rival Pompey in Caesar's civil wa ...

consulted him while he was designing the

Julian calendar The Julian calendar is a solar calendar of 365 days in every year with an additional leap day every fourth year (without exception). The Julian calendar is still used as a religious calendar in parts of the Eastern Orthodox Church and in parts ...

Biography

Little is known about him apart from Pliny's ''

''. Sosigenes appears in Book 18, 210-212: Sosigenes is credited with work on the orbit of Mercury, which is described by Pliny in book 2, ''Natural History'': The introduction of the Julian year occurred in 46 BC. This particular year lasted 445 days in Rome to correct the erroneous old

Roman calendar The Roman calendar was the calendar used by the Roman Kingdom and Roman Republic. Although the term is primarily used for Rome's pre-Julian calendars, it is often used inclusively of the Julian calendar established by Julius Caesar in 46&nbs ...

, and is thus considered "the longest year in history".

Cultural depiction

Since the 18th century, the classicists have added to the name of Sosigenes, to distinguish it from others, the origin: "of Alexandria". However, no ancient source calls him that, or indicates that he was an Alexandrian. The misattribution may be from the fusion of two pieces of news about the reform of the Roman calendar at the initiative of Julius Caesar, namely: the indication by

Appian Appian of Alexandria (; ; ; ) was a Greek historian with Roman citizenship who prospered during the reigns of the Roman Emperors Trajan, Hadrian, and Antoninus Pius. He was born c. 95 in Alexandria. After holding the senior offices in the pr ...

Cassius Dio Lucius Cassius Dio (), also known as Dio Cassius ( ), was a Roman historian and senator of maternal Greek origin. He published 80 volumes of the history of ancient Rome, beginning with the arrival of Aeneas in Italy. The volumes documented the ...

and

Macrobius Macrobius Ambrosius Theodosius, usually referred to as Macrobius (fl. AD 400), was a Roman provincial who lived during the early fifth century, during late antiquity, the period of time corresponding to the Later Roman Empire, and when Latin was ...

that the reform was based on "Egyptian teachings" together with the news from Pliny that Sosigenes was one of the experts consulted by Caesar for the adaptation of the calendar. The oldest mention of Sosigenes of Alexandria appears in the work of Le Fèvre de Morsan ''Des Moeurs et des Usages des Romains'', published in 1739. Sosigenes was portrayed by Hume Cronyn in the 1963 movie ''

Cleopatra Cleopatra VII Thea Philopator (; The name Cleopatra is pronounced , or sometimes in both British and American English, see and respectively. Her name was pronounced in the Greek dialect of Egypt (see Koine Greek phonology). She was ...

''. This portrayal is heavily fictionalized: he serves as

's tutor/adviser and later her envoy to Rome. He is ultimately murdered in the Forum by

Octavian Gaius Julius Caesar Augustus (born Gaius Octavius; 23 September 63 BC – 19 August AD 14), also known as Octavian (), was the founder of the Roman Empire, who reigned as the first Roman emperor from 27 BC until his death in ...

, commencing his war against Egypt. None of those events is present in the historical record, and they were invented for the film.

References

* {{Authority control Ancient Greek astronomers Julian calendar Roman-era Alexandrians 1st-century BC astronomers

Biography

Cultural depiction

See also

References