2. Son of Antipater and brother of Cassander, king of Macedonia. He is first mentioned in the year B. C. 313, when he was left by his brother in the command of Chalcis, to make head against Ptolemy, the general of Antigonus, when Cassander himself was recalled to the defence of Macedonia. (Diod. 19.77.) Again, in B. C. 302, when the general coalition was formed against Antigonus, Pleistarchus was sent forward by his brother, with an army of 12,000 foot and 500 horse, to join Lysimachus in Asia. As the Hellespont and entrance of the Euxine was occupied by Demetrius, he endeavoured to transport his troops from Odessus direct to Heracleia, but lost by far the greater part on the passage, some having been capturned by the enemy's ships, while others perished in a storm, in which Pleistarchus himself narrowly escaped shipwreck. (Id. 20.112.) Notwith-standing this misfortune, he seems to have rendered efficient service to the confederates, for which he was rewarded after the battle of Ipsus (B. C. 301) by obtaining the province of Cilicia, as an independent government. This, however, he did not long retain, being expelled from it in the following year, by Demetrius, almost without opposition. (Plut. Demetr. 31.) Hereupon he returned to his brother Cassander, and from this time we hear no more of him. Pausanias mentions him as having been defeated by the Athenians in an action in which he commanded the cavalry and auxiliaries of Cassander; but the period at which this event took place is uncertain. (Paus. 1.15.1.) It is perhaps to him that the medical writer, Diocles of Carystus, addressed his work, which is cited more than once by Athenaeus, as τὰ πρὸς Πλείσταρχον Ὑγιεινά. (Athen. 7.320d, 324, f.)