 Sthenelus was the driver of Diomedes’ chariot and probably his closest friend.All the troops from Argos, Tiryns, Troezen and some other cities were headed by Diomedes.Although he was the youngest of the Achaean kings, Diomedes is considered the most experienced leader by many scholars (he had fought more battles than others, including the most important war expedition before the Trojan War – even old Nestor had not participated in such military work).