Agasias was the name of several different people in Classical history, including two different Greek sculptors.
Agasias of Arcadia, a warrior mentioned by Xenophon
Agasias (Gr. Ἀγασίας) was a Stymphalian of Arcadia who was frequently mentioned by Xenophon as a brave and active officer in the army of the Ten Thousand. He was an acquaintance of both Hieron and Xenophon. In his youth, he achieved an Olympic victory, and hired Pindar to compose a song of celebration. He was wounded while fighting against Asidates.
Agasias, son of Dositheus
Agasias (Ancient Greek: Ἀγασίας), son of Dositheus, was an ancient Greek sculptor of Ephesus. One of the productions of his chisel, the statue known by the name of the Borghese Gladiator, is still preserved in the gallery of the Louvre. This statue was discovered among the ruins of a palace of the Roman emperors on the site of the ancient Antium. From the attitude of the figure it is clear that the statue represents not a gladiator, but a warrior contending with a mounted combatant. Friedrich Thiersch conjectured that it was intended to represent Achilles fighting with Penthesilea.
The only record existing about the artist is the inscription on the pedestal of the statue; nor are there any data for ascertaining the age in which he lived, except the style of art displayed in the work itself, which competent judges think cannot have been produced earlier than the 4th century BC.
It is not quite clear whether the Agasias who is mentioned as the father of Heraclides was the same as the author of the Borghese statue, or a different person.
There was another sculptor of the same name, also an Ephesian, the son of Menophilus. He is mentioned in a Greek inscription, from which it appears that he exercised his art in Delos while that island was under Roman sway; probably some time about 100 BC.