Suda

The Suda or Souda (Greek: Σοῦδα) is a massive 10th century Byzantine encyclopedia of the ancient Mediterranean world, formerly attributed to an author called Suidas. It is an encyclopedic lexicon, written in Greek, with 30,000 entries, many drawing from ancient sources that have since been lost, and often derived from medieval Christian compilers. The derivation is probably from the Byzantine Greek word souda, meaning "fortress" or "stronghold," with the alternate name, Suidas, stemming from an error made by Eustathius, who mistook the title for the proper name of the author.

The Suda is somewhere between a grammatical dictionary and an encyclopedia in the modern sense. It explains the source, derivation, and meaning of words according to the philology of its period, using such earlier authorities as Harpocration and Helladios. There is nothing especially important about this aspect of the work. It is the articles on literary history that are valuable. These entries supply details and quotations from authors whose works are otherwise lost. They use older scholia to the classics (Homer, Thucydides, Sophocles, etc.), and for later writers, Polybius, Josephus, the Chronicon Paschale, George Syncellus, George Hamartolus, and so on.

This lexicon represents a convenient work of reference for persons who played a part in political, ecclesiastical, and literary history in the East down to the tenth century. The chief source for this is the encyclopedia of Constantine VII Porphyrogenitus (912-59), and for Roman history the excerpts of John of Antioch (fifth century). Krumbacher (Byzantinische Literatur, 566) counts two main sources of the work: Constantine VII for ancient history, and Hamartolus (Georgios Monachos) for the Byzantine age.