information:extraction, structural:expansion
Antigonid period military

The Macedonian army continued to evolve under the Antigonid dynasty. It is uncertain how many men were appointed as somatophylakes, which numbered eight men at the end of Alexander the Great's reign, while the hypaspistai seem to have morphed into assistants of the somatophylakes. At the Battle of Cynoscephalae in 197 BC, the Macedonians commanded some 16,000 phalanx pikemen. Alexander the Great's royal squadron of companion cavalry contained 800 men, the same number of cavalrymen in the sacred squadron (Latin: sacra ala; Greek: hiera ile) commanded by Philip V of Macedon during the Social War of 219 BC. The regular Macedonian cavalry numbered 3,000 at Callinicus, which was separate from the sacred squadron and royal cavalry. While Macedonian cavalry of the 4th century BC had fought without shields, the use of shields by cavalry was adopted from the Celtic invaders of the 270s BC who settled in Galatia, central Anatolia.

Thanks to contemporary inscriptions from Amphipolis and Greia dated 218 and 181 BC, respectively, historians have been able to partially piece together the organization of the Antigonid army under Philip V. From at least the time of Antigonus III Doson, the most elite Antigonid-period infantry were the peltasts, lighter and more maneuverable soldiers wielding peltai javelins, swords, and a smaller bronze shield than Macedonian phalanx pikemen, although they sometimes served in that capacity. Among the peltasts, roughly 2,000 men were selected to serve in the elite agema vanguard, with other peltasts numbering roughly 3,000. The number of peltasts varied over time, perhaps never more than 5,000 men. They fought alongside the phalanx pikemen, divided now into chalkaspides (bronze shield) and leukaspides (white shield) regiments.

The Antigonid Macedonian kings continued to expand and equip the navy. Cassander maintained a small fleet at Pydna, Demetrius I of Macedon had one at Pella, and Antigonus II Gonatas, while serving as a general for Demetrius in Greece, used the navy to secure the Macedonian holdings in Demetrias, Chalkis, Piraeus, and Corinth. The navy was considerably expanded during the Chremonidean War (267–261 BC), allowing the Macedonian navy to defeat the Ptolemaic Egyptian navy at the 255 BC Battle of Cos and 245 BC Battle of Andros, and enabling Macedonian influence to spread over the Cyclades. Antigonus III Doson used the Macedonian navy to invade Caria, while Philip V sent 200 ships to fight in the Battle of Chios in 201 BC. The Macedonian navy was reduced to a mere six vessels as agreed in the 197 BC peace treaty that concluded the Second Macedonian War with the Roman Republic, although Perseus of Macedon quickly assembled some lemboi at the outbreak of the Third Macedonian War in 171 BC.