The Achaemenid chiliarch par excellence: commander of guard infantry, cavalry or both?

There has been recent debate over whether the commander of the Great King's infantry or cavalry bodyguard, the melophoroi or 'Apple Bearers' and the syngeneis hippeis or 'Kinsmen Cavalry' respectively, was the preeminent chiliarch in Achaemenid Persia. This study assembles the evidence and reinforces the traditional view that there is little cause to associate the commander of the syngeneis with the roles normally attributed to the office of the so-called 'court chiliarch'. Indeed, a close inspection of the source material, together with broader reflection on the status of Achaemenid infantry vis-à-vis that of the cavalry, leads to the conclusion that it is unlikely that their commander normally held a position of equivalent seniority.