(), son of Demetrius Poliorcetes and
Phila (the daughter of Antipater), and grandson of Antigonus, king of Asia. [ANTIGONIDAE.] When his father Demetrius was driven out of Macedonia by
Pyrrhus, in B. C. 287, and crossed over into Asia, Antigonus
remained in Peloponnesus ; but he did not assume the title of king of Macedonia till after his
father's death in Asia in B. C. 283. It was some years, however,
before he obtained possession of his paternal dominions. Pyrrhus was deprived of the kingdom
by Lysimachus (B. C. 286); Lysimachus was succeeded by Seleucus
(280), who was murdered by Ptolemy Ceraunus. Ceraunus shortly after fell in battle against the
Gauls, and during the next three years there was a succession of claimants to the throne.
Antigonus at last obtained possession of the kingdom in 277, notwithstanding the opposition of
Antiochus, the son of Seleucus, who laid claim to the crown in virtue of his father's
conquests. But he withdrew his claim on the marriage of his half-sister, Phila, with
Antigonus. He subsequently defeated the Gauls, and continued in possession of his kingdom till
the return of Pyrrhus from Italy in 273, who deprived him of the whole of Macedonia, with the
exception of a few places. He recovered his dominions in the following year (272) on the death
of Pyrrhus at Argos, but was again deprived of them by Alexander, the son of Pyrrhus.
Alexander, however, did not retain possession of the country long, and was compelled to retire
by the conquests of Demetrius, the brother or son of Antigonus, who now obtained part of
Epeirus in addition to his paternal dominions. He subsequently attempted to prevent the
formation of the Achaean league, and died in B. C. 239, at the age
of eighty, after a reign of forty-four years. He was succeeded by Demetrius II. (Plut.Demetr. 51, Pyrrhus, 26; Justin, 24.1, 25.1_3, 26.2; Plb. 2.43, &c.; Lucian, Macrob. 100.11; Niebuhr, Kleine Schriften, p. 227,
&c.) Antigonus' surname Gonatas is usually derived from Gonnos or Gonni in Thessaly, which
is supposed to have been the place of his birth or education. Niebuhr (l.c.), however, remarks, that Thessaly did not come into his father's possession till
Antigonus had grown up, and he thinks that Gonatas is a Macedonian word, the same as the
Romaic γονατὰς, which signifies an iron plate protecting
the knee, and that Antigonus obtained this surname from wearing such a piece of defensive
armour.