Callias in Harpers Dictionary of Classical Antiquities

（Καλλίας) and Hippon īcus (Ἱππόνικος). A noble Athenian family, celebrated for their wealth. They enjoyed the hereditary dignity of torch-bearer at the Eleusinian Mysteries, and claimed descent from Triptolemus. The first member of this family of any note was the Callias who fought at the battle of Marathon, B.C. 490, and was afterwards ambassador from Athens to Artaxerxes, and, according to some accounts, negotiated a peace with Persia, B.C. 449, on terms most humiliating to the latter. On his return to Athens he was accused of having taken bribes, and was condemned to a fine of fifty talents. His son, Hipponicus, was killed at the battle of Delium in B.C. 424. It was his divorced wife, and not his widow, whom Pericles married. His daughter Hippareté was married to Alcibiades. Callias, son of this Hipponicus by the lady who married Pericles, dissipated all his ancestral wealth on sophists, flatterers, and women. The scene of Xenophon's Banquet, and also that of Plato's Protagoras, is laid at his house.