(), king or dynast of Caria, in the reign of
Artaxerxes III. He was appointed by the Persian king to command the naval forces destined to
take part in the war against Evagoras of Cyprus (Theopomp. apud Phot. p.
120 a; Diod. 14.98); but the operations of the war were at that
time allowed to linger; and it appears that Hecatomnus himself shared in the spirit of
disaffection towards Persia at that time so general; as when hostilities were at length
resumed in earnest against Evagoras, he not only took no part in support of the Persian
monarchy, but secretly supplied Evagoras with sums of money to raise mercenary troops. (Diod. 15.2.) No notice, however, seems to have been taken of this act
of treachery, a circumstance for which the dis organised state of the Persian monarchy will
fully account : and Hecatomnus continued to hold possession of Caria in a state of virtual
independence until his death. The date of this cannot be ascer tained with certainty, but we
learn from Isocrates (Panegyr. p. 74 d) that he was still
ruling in B. C. 380. Clinton has suggested that the date B. C. 279, assigned by Pliny for the death of Maussolus, was in fact that
of the commencement of his reign, and the death of his father, Hecatomnus. (Plin. Nat. 36.6.) He left three sons, Maussolus, Idrieus, and
Pixodarus, all of whom, in their turn, succeeded him in the sovereignty; and two daughters,
Artemisia and Ada, who were married, according to the Asiatic custom, to their brothers
Maussolus and Idrieus. (Strab. xiv. p.6.56; Arr. Anab. 1.23.) Hecatomnus was a native of Mylasa, and made that
city his capital and the seat of his government : hence we find on his coins the figure of
Zeus Labrandenos (represented as walking and carrying a bipennis over his shoulder), from the
celebrated temple of that name near Mylasa. (Strab. xiv.
p.659; Eckhel, vol. ii. p. 596.)