Hetairenreiterei
The Companion cavalry, or "Hetairoi" (), were the elite arm of the Macedonian army, and were the offensive force that made the decisive attack in most of the battles of Alexander the Great. They were unmatched in the pre-stirrup Ancient world in their ability to retain their seat and the control of their weapons through the impact of a charge. Along with Thessalian cavalry contingents, the Companions — raised from landed nobility — made up the bulk of the Macedonian heavy cavalry. Central Macedonia was good horse-rearing country and cavalry was prominent in Macedonian armies from early times. However, it was the reforms in organisation, drill and tactics introduced by Philip II that transformed the Companion cavalry into a battle-winning force, especially the introduction of, or increased emphasis on, the use of a lance and shock tactics. Coinage indicates that from an early period the primary weapons used by Macedonian cavalry were a pair of javelins. This remained true through to the reign of Archelaus I (413–399). Subsequently, despite the adoption of the lance, it is highly probable that the Companion cavalry continued to employ javelins when on scouting or skirmishing missions.