(Δορίμαχος), less properly DORY'MACHUS (Δορν́μαχος), a native of Trichonium, in Aetolia, and son of Nicostratus, was sent out, in B. C. 221, to Phigalea, on the Messenian border, with which the Aetolians had a league of sympolity, ostensibly to defend the place, but in reality to watch affairs in the Peloponnesus with a view of fomenting a war, for which his restless countrymen were anxious. A number of freebooters flocked together to him, and he connived at their plundering the territory of the Messenians, with whom Aetolia was in alliance. All complaints he received at first with neglect, and afterwards (when he had gone to Messene, on pretence of investigating the matter) with insult. The Messenians, however, and especially Sciron, one of their ephori, behaved with such spirit that Dorimachus was compelled to yield, and to promise satisfaction for the injuries done; but he had been treated with indignity, which he did not forget, and he resolved to bring about a war with Messenia. This he was enabled to do through his kinsman Scopas, who administered the Aetolian government at the time, and who, without waiting for any decree of the Assembly, or for the sanction of the select council (Ἀπόκλητολ; see Plb. 20.1; Liv. 35.34), commenced hostilities, not against Messenia only, but also against the Epeirots, Achaeans, Acarnanians, and Macedonians. In the next year, B. C. 220, Dorimachus invaded the Peloponnesus with Scopas, and defeated Aratus, at Caphyae. [See p. 255a.] He took part also in the operations in which the Aetolians were joined by Scerdiläidas, the Illyrian,--the capture and burning of Cynaetha, in Arcadia, and the baffled attempt on Cleitor,--and he was one of the leaders of the unsuccessful expedition against Aegeira in B. C. 219. In the autumn of the same year, being chosen general of the Aetolians, he ravaged Epeirus, and destroyed the temple at Dodona. In B. C. 218 he invaded Thessaly, in the hope of drawing Philip away from the siege of Palus, in Cephallenia, which he was indeed obliged to relinquish, in consequence of the treachery of Leontius, but he took advantage of the absence of Dorimachus to make an incursion into Aetolia, advancing to Thermum, the capital city, and plundering it. Dorimachus is mentioned by Livy as one of the chiefs through whom M. Valerius Laevinus, in B. C. 211, concluded a treaty of alliance with Aetolia against Philip, from whom he vainly attempted, in B. C. 210, to save the town of Echinus, in Thessaly. In B. C. 204 he and Scopas were appointed by the Aetolians to draw up new laws to meet the general distress, occasioned by heavy debts, with which the two commissioners themselves were severely burdened. In B. C. 196 Dorimachus was sent to Egypt to negotiate terms of peace with Ptolemy V. (Epiphanes), his mission probably having reference to the conditions of amity between Ptolemy and Antiochus the Great, to whom the Aetolians were now looking for support against Rome. (Plb. 4.3_13, 16_19, 57,58, 67, 77; 5.1.3, 4-9. 11, 17; 9.42; 13.1; xviii 37; 20.1; Fragm. Hist. 68; Liv. 26.24; Brandstäter, Gesch. des Aetol. Landes, p. 342, &c.)