Antigonus II Gonatas (c. 319 BC—239 BC) was a Macedonian king, the son of Demetrius I Poliorcetes, and grandson of Antigonus I Monophthalmus.

On the death of his father (283 BC), he assumed the title "king of Macedonia", but did not obtain possession of the throne until 276 BC, after it had been successively in the hands of Pyrrhus, Lysimachus, Seleucus, and Ptolemy Ceraunus.

Ceraunus was killed by the invading Gauls in 279 BC, and the Macedonian kingdom lapsed into anarchy for two years. Gonatas defeated an army of Gauls in 277 BC in the Battle of Lysimachia, and that won him enough credit to claim the throne of Macedon.

He continued in undisputed possession of Macedonia till 274 BC, when Pyrrhus returned from Italy. Pyrrhus launched an attack on the Macedonian army, then convinced it to support him rather than Gonatas. When Pyrrhus was killed adventuring in the Peloponnese in 272 BC, Gonatas recovered his dominions. He was again (between 263 BC and 255 BC) driven out of the kingdom by Alexander, the son of Pyrrhus, and again recovered.

The latter part of his reign was comparatively peaceful, and he gained the affection of his subjects by his honesty and his cultivation of the arts. He gathered round him distinguished literary men — philosophers, poets, and historians. He died in his eightieth year, and the forty-fourth of his reign. His surname "Gonatas", the meaning of which is lost, was usually derived by later Greek writers from the name of his supposed birthplace, Gonni (Gonnus) in Thessaly. More recent philologists suggest that it means "knock-kneed".

References

• Plutarch, Demetrius, Pyrrhus, Aratus
• Justin xxiv. I; xxv. I-3;
• Polybius ii. 43-45, ix. 29, 34
• Janice J. Gabbert, Antigonus II Gonatas: A Political Biography (1997)