Diodorus of Sicily: Greek historian, author of the Library of World History. His activities can be dated between 60 and 30 BCE.


Roman, third quarter of the first century BCE
Roman, third quarter of the first century BCE

The year of Diodorus' birth and death cannot be established exactly, but his work offers several clues. For example, he mentions that Caesar (i.e., Octavian) "removed the citizens of Tauromenium from their native state and the city received a colonia".note This almost certainly refers to an incident during or shortly after the war between the members of the Second Triumvirate and Sextus Pompeius, in 36 BCE. Diodorus must have died after this event.

Diodorus also mentions that in his days, the Macedonians were still rulers of Egypt, which suggests that he published his work shortly before 30, when Octavian defeated Mar Antony and Cleopatra, the last Ptolemaic queen, and conquered the ancient country along the Nile.

On the other end of the spectrum, Diodorus mentions how he witnessed that a group of Egyptians lynched a Roman who had accidentally killed a holy cat.note This happened "before king Ptolemy XII Auletes had been recognized by the Romans". He was, however, called "friend" in the year of the consulship of Julius Caesar (59), so we can be confident that Diodorus was in Alexandria by then. If we assume that he did his historical research and writing between 65/60 and 35/30, we cannot be far off the mark.

We don't know much about other aspects of his life either. He was born in Agyrium on Sicily, which was, according to the Roman orator Cicero, an impoverished town. Our writer understood some Latin, although he continued to make mistakes. He visited Egypt and Rome, and claims to have traveled extensively, but he nowhere shows acquaintance with important cities like Athens, Miletus, Ephesus, or Antioch. His description of Nineveh as a city on the Euphrates is simply wrong, and so is his statement that Chalkidike is near the Hellespont.note

On the other hand, he must have been a wealthy man, because he mentions no literary patron and could afford to spend thirty years reading and writing.note He makes no reference to any occupation of public offices, so he seems to have been a bookish man, a historian who carefully studied, excerpted, and reworked the works of earlier scholars. This method is not unlike that of his younger Roman contemporary Livy, who started to write more or less at the moment when Diodorus published the Library of World History.

World History

For a man who lived through the decade between 70 and 60, the theme of a world history was obvious. As a young man, Diodorus had seen how the entire Mediterranean world had been united by the Romans, with campaigns conducted by general Pompey the Great, who had pacified large parts of Hispania in the west and the entire east, where he had defeated the Cilician pirates, conquered large parts of Anatolia, added the remains of the once powerful Seleucid Empire to the Roman empire, an annexed Judaea as well.

Although Diodorus twice announces that he wanted to continue his World History until the moment that Caesar had conquered Britain and reached the edges of the earth, it seems that the end was in fact the year 59: Caesar's consulship, the ratification of Pompey's oriental acts, the conclusion of First Triumvirate, and the beginning of Caesar's Gallic War and rise to power. The ratification of Pompey's eastern measures was a fitting conclusion: from now on, the world was a unity. Telling the story of later events (the Roman civil wars) was politically unsafe for a man writing in the thirties BCE.

Although Diodorus must have seen the rise of Rome as something inevitable, he does not really like the new masters of the Roman world. He never fails to point out the cruelty, rapacity, and impiety of the Romans. He had no reason to: both Sicily and Alexandria had been the scene of a civil war.

Diodorus' World History was, in his own words, "an immense work" that consisted of forty books, of which 1-5 and 11-20 survive completely. (The last complete copy vanished when the Turks sacked Constantinople in 1453.) Fragments from the other volumes are known from Byzantine excerpts and are sufficiently well understood to know that Diodorus used histories by Polybius of Megalopolis and the Stoic philosopher Posidonius of Apamea. The first half of the Library of World History can be summarized as follows:

1 Myths and kings of ancient Egypt Hecataeus of Abdera
2 Assyria, India, Scythia, Arabia Ctesias; Megasthenes
3 Ethiopia and Libya; birth of the gods Dionysius Scytobrachion
4 Greek gods and heroes Dionysius S. & Euhemerus
5 The islands and peoples of the west Timaeus of Tauromenium
6 Greek legends Dionysius S. & Euhemerus
7 The Trojan War Dionysius Scytobrachion
8 Archaic age ?
9 Archaic age (until c.540); the Seven sages a/o Herodotus
10 Archaic age (c.540-481) a/o Herodotus
11 Persian war; Pentacontaetia (480-451) Herodotus; Ephorus
12 Pentacontaetia; Archidamian War (450-416) Ephorus
13 Sicilian Expedition; Ionian War (415-405) Ephorus
14 Corinthian war (404-387) Ephorus
15 Rise of Thebes (386-361) Ephorus
16 Philip of Macedonia (360-336) Theopompus
17 Alexander the Great (335-324/3) Cleitarchus
18 Diadochi (323-318) Hieronymus of Cardia
19 Diadochi (318-311) Hieronymus of Cardia
20 Diadochi (310-302) Hieronymus of Cardia
21 Fragments, including the death of Agathocles (301-c.285)
22 Fragments, including the Gallic attack on Macedonia and Delphi, and Mamertine and Roman cruelties in Messina (c.280-264)
23 Fragments, including the First Punic War (264-250)
24 Fragments, including the First Punic War (250-241)
25 Fragments, including the Carthaginian Mercenary War; Carthaginian advances in Iberia (242-222)
27 Fragments, including Nabis of Sparta and the second half of the Second Punic War (211-c.200)
28 Fragments, including Philip V of Macedonia and the Second Macedonian War (204-195)
29 Fragments, including the Syrian War and Third Macedonian War (195-172)
30 Fragments, including the second half of the Third Macedonian War (172-168)
31 Fragments, including the rise of Cappadocia (169-153)
32 Fragments, including the destruction of Carthage and Corinth (153-146)

All these books contain digressions on events in the west, for which Diodorus used good sources: Timaeus of Tauromenium for Sicily, and an excellent Roman annalist for the history of Italy. Although the table above usually mentions one source for each book, it should be noted that Diodorus felt free to introduce bits and pieces from other sources, and reworked his information considerably.

Nineteenth- and twentieth-century scholars (e.g., Mommsen, Schwartz) have criticized Diodorus, who was, in their vision, an uncritical maker of excerpts and a poor historian. Indeed, the Sicilian makes strange mistakes. Yet, this criticism is ill-judged and the latest research offers something of a rehabilitation, stressing that the Sicilian author did what he wanted to do - write an easily accessible world history. The title, Library of World History, proves that Diodorus did not pretend to offer more than a collection of summaries. As a historian, he is simply as good as his sources.

Besides, he knows how to tell a story, although he lacks the speeches that make other ancient historians so entertaining. Yet, he writes in a clear and unaffected style that is usually easy to understand. One brief example of his nice, well-balanced sentences may suffice, a remark about Agathocles, the tyrant of Sicily:

Conferring benefits on many, making encouraging promises to not a few, and by conversing in a friendly fashion with everyone, he gained great favor.note

Theme and Purpose

Diodorus' theme, how disunited cultures were growing to one Mediterranean civilization under Roman rule, is well-worked out and was certainly appreciated by his contemporaries. For example, we know that among his readers were Pliny the Elder (who says that unlike other anthologies, the work of Diodorus has an honest title), Aelian, Athenaeus, and the Christian author Eusebius.

Why did Diodorus spend 30 years writing a not highly original work? He explains it in his introduction.note History is useful. It is the teacher of humankind because it transmits experience. Readers are inspired by noble examples, and will understand the true power and justice of the gods, who punish evil acts. Therefore, a historian is a benefactor to society: he tells a delightful story and instructs.

In other words, Diodorus is like any other wealthy Greek or Roman: he accepted his responsibility for his community, and although he never occupied an office and is not known to have donated a nice building to his hometown, he gave his fellow-man something important.


To us, he is a very important source. After all, the remains of the Library of World History are the largest surviving corpus of any ancient Greek historian, yes, books 11-20 are the only surviving continuous account of the Greek "classical" age. It would be impossible to write a history of Sicily without Diodorus, and for the period 480-431 (the Pentacontaetia) and the age of the Diadochi he is our main source. His description of Alexander's last weeks in Babylon is high-quality material, and it has recently been shown by assyriologists that no other Greek author shows so much understanding of Babylonian civilization and the teaching of the Chaldaeans (which is also a compliment to Diodorus' source, Cleitarchus).

Finally, it should be noted that although he makes mistakes in synchronizing Greek and Roman chronology, Diodorus' list of Roman magistrates is the best one we have - he ignores the errors of the Varronian Chronology. The Sicilian historian may not be among the greatest authors of Antiquity, but no one studying Antiquity can afford to ignore his work.


This page was created in 2004; last modified on 22 September 2020.