The Macedonian Pieria was a narrow strip of country on the southeastern coast of Macedonia, extending from the mouth of the Peneus in Thessaly to the Haliacmon, and bounded on the west by Mount Olympus and its offshoots.
Pierus was of this opinion either because it seemed to him wiser, or because an oracle so ordered, or having so learned from one of the Thracians.
There are some who say that Pierus himself had nine daughters, that their names were the same as those of the goddesses, and that those whom the Greeks called the children of the Muses were sons of the daughters of Pierus.
It is not known if Pierus did these changes because they seemed to him wiser, or if he followed an oracle, or if he had learned so from the Thracians.
Thus the MUSES are sometimes called PIERIDES, but otherwise this is the name of nine sisters, daughters of Pierus, who defied the MUSES in a contest of song and, having been defeated, were turned into magpies, greenfinches, goldfinches, ducks, and other birds [for the ALOADS see Zeus].
Clio 1 consorted with King Pierus of Pella (Macedonia), giving birth to Hyacinthus 1 and Polyboea 1, the girl who was carried to heaven.