Dictionary of Greek and Roman Antiquities edited William Smith (1870). This edition was scanned by the University of Michigan's project The Making of America. The text on this site underwent a separate OCR process.
Smith's Dictionary of Greek and Roman Biography and Mythology is a 3,700-page compendium of 19th century classical scholarship. The Dictionary covers a dazzling array of historical characters, authors, gods and heroes in great detail and depth.
The work is a companion to Smith's Dictionary of Greek and Roman Antiquities (online here) and Dictionary of Greek and Roman Geography (coming soon). Although over a century old, it remains valuable. Interpretations have changed, of course, but Smith's evidence is largely the same as scholars have today. In detail, depth and particularly citation of ancient texts, Smith's work compares very favorably with its contemporary equivalent, the Oxford Classical Dictionary.
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