From BiblePortal Wikipedia

Hastings' Dictionary of the Bible [1]

Alcimus (the Greek for ‘valiant,’ suggested by the Hebrew Eliakim , ‘God sets up’) was son or nephew of Jose ben-Joeser, pupil to Antigonus of Socho (b.c. 190). Antiochus V. (Eupator), king of Syria, appointed him high priest (b.c. 162). Either because he was not of high priestly family (though of the stock of Aaron, 1Ma 7:14 ), or, more probably, from his Hellenizing tendencies, his appointment was stoutly opposed by Judas Maccabæus, and received hut scanty recognition at Jerusalem. Demetrius Soter, cousin and successor to Antiochus, in response to Alcimus’s solicitations, reinstated him by the means of Nicanor, the Syrian general. He now received, moreover, considerable local support from the Hellenizing party. It was not, however, till the defeat and death of Judas at Elasa that he was in a position to commence his Hellenizing measures, and shortly afterwards he died of paralysis (b.c. 160).

A. W. Streane.

Cyclopedia of Biblical, Theological and Ecclesiastical Literature [2]

( ῎Αλκιμος , Strong, or perh. only a Graecized form of the Hebrew Eliakim), called, also, Jacimus, i e. Joakim ( Ι᾿Άκειμος , Josephus, Ant. 12, 9, 7), a Jewish priest ( 1 Maccabees 7:14) who, apostatizing to the Syrians, was appointed high-priest (B.C. 162) by King Demetrius, as successor of Menelaus ( 1 Maccabees 7:5), by the influence of Lysias, though not of the pontifical family (Josephus, Ant. 12, 9, 7; 20:10;  1 Maccabees 7:14), to the exclusion of Onias, the nephew of Menelaus, having already been nominated by Antiochus Eupator (Josephus, Ant. 12, 9, 7; comp. Selden, De success. in pontyf. p. 150), and instated into office by force of arms by the Syrian general Bacchides ( 1 Maccabees 7:9 sq.). According to a Jewish tradition (Bereshith R. 65), he was "sister's son of Jose ben-Joeser," chief of the Sanhedrim, whom he afterward put to death (Raphall, Hist. of Jews, 1, 245, 308). At first he attached many of the patriots to his cause by fair promises ( 1 Maccabees 7:18 sq.), but soon alienated by his perfidy not only these but his other friends, so that he was at length compelled to flee from the opposition of Judas Maccabeus to the Syrian king ( 1 Maccabees 7:25;  2 Maccabees 14:3 sq.). Nicanor, who was sent with a large army to assist him, was routed and slain by the Jewish patriots ( 1 Maccabees 7:43;  2 Maccabees 15:37), B.C. 161. Bacchides immediately advanced a second time against Jerusalem with a large army, routed Judas, who fell in the battle (B.C. 161), and reinstated Alcimus. After his restoration, Alcimus seems to have attempted to modify the ancient worship, and, as he was engaged in pulling down "the walls of the inner court of the sanctuary" (i.e. which separated the court of the Gentiles from it; yet see Grimm, Comment. on  1 Maccabees 9:54), he was "plagued" (by paralysis), and

"died at that time," B.C. 160 (Josephus, Ant. 12, 9, 5; 12:10; 1 Maccabees 7, 9; comp. 2 Maccabees 14, 15; see Ewald, Gesch. des Volkes Isr. 4, 365 sq.).

International Standard Bible Encyclopedia [3]

al´si - mus ( אליקיּם , 'elyāḳūm , "God will rise"; Ἄλκιμος , Álkı̄mos , "valiant"): A high priest for three years, 163-161 bc, the record of whose career may be found in 1 Macc 7:4-50; 9:1-57; 2 Macc 14; see also Ant , Xii , 9-11; XX, 10. He was a descendant of Aaron, but not in the high-priestly line (1 Macc 7:14; also Ant , XX, 10); and being ambitious for the office of high priest, he hastened to Antioch to secure the favor and help of the new king, Demetrius, who had just overthrown Antiochus Eupator and made himself king. Alcimus was of the Grecianizing party, and therefore bitterly opposed by the Maccabees. Demetrius sent a strong army under Bacchides to establish him in the high-priesthood at Jerusalem. The favor with which Alcimus was received by the Jews at Jerusalem on account of his Aaronic descent was soon turned to hate by his cruelties. When Bacchides and his army returned to Antioch, Simon Maccabeus attacked and overcame Alcimus, and drove him also to Syria. There he secured from Demetrius another army, led by Nicanor, who, failing to secure Simon by treachery, joined battle with him, but was defeated and killed. A third and greater army, under Bacchides again, was dispatched to save the falling fortunes of Alcimus. Now Simon was overwhelmed and slain, Alcimus established as high priest and a strong force left in Jerusalem to uphold him. But he did not long enjoy his triumph, since he died soon after from a paralytic stroke.