Thirlwairs Greece, vol. v. p. 275, not.). He com-
manded a division of the Phocian army under Phi-
lomelus, in the action at Tithorea, in which the
latter perish6d ; and after the battle gathered to-
gether the remains of the Phocian army, with
which he effected his retreat to Delphi. An
assembly of the people was now held, in which Ono-
marchus strongly urged the prosecution of the war,
in opposition to the counsels of the more moderate
party, and succeeded in obtaining his own nomi-
nation to the chief command in the place of Philo-
melus, B. c. 353. He was, however, far from
imitating the moderation of his predecessor: he
confiscated the property of all those who were
opposed to him, and squandered without scruple the
sacred treasures of Delphi. The latter enabled
him not only to assemble and maintain a large
body of mercenary troops, but to spend large sums
in bribing many of the leading persons in the hostile states ; by which means he succeeded in pre-
vailing on the Thessalians to abandon their allies,
and take up a neutral position. Thus freed from
his most formidable antagonists, he was more than
a match for his remaining foes. He now invaded
Locris, took the town of Thronium, and compelled
that of Amphissa to submit ; ravaged the Dorian
Tetrapolis, and then turned his arms against
Boeotia, where he took Orchomenus and laid siege
to Chaeroneia, but was compelled to retreat with-
out effecting anything more. His assistance was
now requested by Lycophron, tyrant of Pherae,
who was attacked by Philip, king of Macedonia ;
and he at first sent his brother Phayllus into
Thessaly with an army of 7000 men. But Phayllus
having been defeated by Philip, Onomarchus
marched with his whole forces to the support of
Lycophron, defeated Philip in two successive
battles, and drove him out of Thessaly. He next
turned his arms a second time against the Boeotians,
whom he defeated in a battle, and took the city of
Coroneia, when he was recalled once more to the
assistance of Lycophron, against Philip, who had
again invaded Thessaly. Onomarchus hastened to
support his ally with an army of 20,000 foot and
500 horse, but was met by Philip at the head of
a force still more numerous, and a pitched battle
ensued, in which the superiority of the Thessalian
eavalry decided the victory in favour of the king.
Onomarchus himself, with many of the fugitives,
plunged into the sea in hopes to reach by swim-
ming the Athenian ships under Chares, which were
lying off the shore, but perished in the waves, or,
according to Pausanias, by the darts of his own
soldiers. His body fell into the hands of Philip,
who caused it to be crucified, as a punishment for
his sacrilege. His death took place in B. c. 352
(Diod. xvi. 31—33, 35, 56, 61 ; Pans. x. 2. § 5 ;
Justin, viii. 1, 2 ; Polyaen. ii. 38 ; Ephorus, fr.
153, ed, Didot ; Ores. iii. 12 ; Wesseling, ad
Diod. xvi. 35 ; Dem. de Fals. Leg. p. 443). We
are told that Onomarchus was a man of luxu-
rious habits, and that he made use of the sacred
treasures, not only for the purposes of the state,
but to minister to his own pleasures (Theopomp. ap.
Athen. xiii. p. 605) ; but it is difficult to know what
value to attach to such statements ; the religious
character assumed by the enemies of the Phocians
having led them to load with obloquy the memory
of all the leaders of that people. [E. H. B.]
ONOMASTUS ('OvoVoo-Tos), a confidential officer of Pliilip V. of Ma^edon, for whom he held the government of the sea-coast of Tlirace, and whose instrument he was, together with Cassan- DER [No. 4], in the massacre of the Maronites. Appius Claudius, and the other Roman commis- sioners, required that Philip should send Onomastus and Cassander to Rome to be examined about the massacre ; whereupon the king despatched Cas- sander, and had him poisoned on the way, but persisted in declaring that Onomastus had not been in or near Maroneia at the time ; the fact being (as Polybius and Livy tell us) that he was too deep in the royal secrets to be trusted at Rome. We hear again of Onomastus as one of the two assessors of Philip at the private trial of De- metrius, for the alleged attempt on the life of his brother Perseus, B. c. 182. (Polyb. xxiii. 13, 14 ; Liv. xxxix. 34, xl. 8.) [E. E.]
ONOSANDER {'Ovdaav^pos), the author of a celebrated work on military tactics, entitled St/jo- Tr)'yiKus Ao7oy, which is still extant. All sub- sequent Greek and Roman writers on the same subjt;ct made this work their text-book (the em- perors Mauricius and Leon did little more than express in the corrupt style of their age what they found in Onosander, whom Leon calls Onesander), and it is even still held in considerable estimation. Count Moritz of Saxony professed to have derived great benefit from the perusal of a translation of it. Onosander appears to have lived about the middle of the first century after Christ. His work is dedi- cated to Q. Veranius, who is generally supposed to be identical witfi the Q. Veranius Nepos who was consul in a. d. 49. Onosander also remarks in his preface that his work was written in time of peace. It might very well have been written, therefore, between a. d. 49 and A. D, 59. If the consul of A. D. 49 was the person to whom the work was de- dicated, it would agree very well with all the other data, that this Veranius accompanied Didius Gallus into Britain, and died before the expiration of a" year.
Onosander was a disciple of the Platonic school of philosophy, and, according to Suidas, besides his work on tactics, wrote one ITept aTpaTrjyrifidTCMSv (unless, as some suppose, the words raKTiKo, irepl crrparii)yrjixdTu>u in Suidas are a description of one and the same work, tlie one still extant), and a commentary on the Republic of Plato. The two latter have perished. In his style he imitated Xenophon with some success. Nothing further is known of his personal history. It is conjectured that he must himself have been engaged in military service. Onosander's work appeared first in a Latin translation by Nicolaus Saguntinus, Rome, 1494. A French translation by Jehan Charrier appeared at Paris in 1546; an ItJilian translation by Fabio Cotta, Venice, 1546 ; and another Latin translation by Joachim Camerarius, in 1595. It was not till 1599 that the Greek text was published, together with the eTTiTrjSeu^uo of Urbicius, published by Nic. Rigaltius, Paris, 1599. The best edition is that by Nic. Schwebel, Nlimberg, 1761, folio. This edition contains the French translation by M. le Baron de Zur-Lauben. In this edition the editor availed himself of the manuscript notes by Jos. Scaliger and Is. Vossius, which are preserved in the library at Leyden. (Fabric. Bill. Graec. vol. iv. p. 336, &c. ; Scholl, Geschichte der Griech. Lit. vol. ii. p. 7 1 2, &c. ; Hoffmann, Lex. Bibl. ) [C. P. M.]
OPE LIUS DIADUMENIA'NUS. [Diadu- MENIANLS.]
