Diodorus Siculus

Diodorus the Sicilian (as his surname means) lived in the first century B.C.E. and wrote a world history, from earliest times to the end of Julius Caesar’s Gallic Wars (54 B.C.E.). Much of the work is lost, but books 11–20 survive fully and provide much information (and some misinformation) about events in Greek history of the 400s and 300s B.C.E. While Diodorus sometimes relies on inferior source material, he provides the best available account for many events of the 300s, such as the wars of the Diadochi.

David Sacks, Encyclopedia of the Ancient Greek World, rev. Lisa R. Brody, rev. ed. (New York: Facts On File, 2005), 112.