Of non-Hellenic origin, Apollo may derive from the interior of Asia Minor; some scholars believe he is derived from Apulunas, the Hittite gate god. Others affirm that Apollo was originally a god of shepherds in the wild regions of the north. A link between the Apollo of Hellenic religion and the more ancient cult of chthonian gods has also been established.

The Romans made their first contact with Apollo partly through the Etruscans and partly through the Greek states of southern Italy. There was a temple to him at Rome as early as 432 BC. In republican times he was venerated chiefly as a god of healing and prophecy; but his status was greatly enhanced by the devotion of Augustus, who erected magnificent temples of Apollo at Actium and on the Palatine. The statue known as the Apollo Belvedere in the Vatican does not represent the Greek conception in the strictly classical age. This is better seen in more ancient figures. From the 5th century BC Apollo was identified with the sun god.

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