An Attic inscription from the early Peloponnesian War records an expedition of thirty triremes, each with five volunteer marines, forty hoplites, ten archers and ten peltasts. Fleets mentioned in Thucydides often averaged more than thirty soldiers per ship, and in fact most of the land battles in the Peloponnesian War were fought against invaders who came by sea. This chapter treats land and sea campaigns in parallel. On campaign Greeks took their armour and weapons, provisions, camping supplies, tools, and medical supplies. In his Acharnians Aristophanes vividly describes what the scene leading up to a fleet's departure would have been like. Greek soldiers also liked camping in sanctuaries, which offered good practical advantages for military camps, since they were prepared to house large numbers of visitors. Naval battles were even rarer than battles on land. The circumvallation sieges were hugely expensive. Greek campaigns simply ended with a general dismissal and a rush to get back pay.

A graphic pitched battle narrative or detailed description of a siege (complete with gruesome embellishments) was a must for any decent history. The tactical flexibility offered by the auxiliary units was especially valuable in the smaller-scale wars of the imperial period, and for frontier and internal security. This applied most of all to the part-mounted equitatae units. Naval battles were more likely to be influenced by the vagaries of weather and wind than land battles, so there could be some delay before conditions allowed a battle to take place. Rome had traditionally been a successful besieger and was able to maintain an army over the winter if necessary. Roman military thinking believed that a pitched battle fought on a fair or level battlefield would bring a certain victory. The tactical manuals provide some insight into how the Romans themselves explained their military success.

This chapter pursues a generic approach to the battles of the Hellenistic and mid-Republican era to analyse them thematically in order to highlight differences and similarities and to cast light on battle as an overall phenomenon. The battles are analysed on two distinct levels: the grand tactical level examining the 'general's battle' of deployment, command and manoeuvre at the level of the army as a whole, and the tactical level. The chapter discusses the 'soldier's battle' at the sharp end itself, focusing on the interaction of differing troop types in actual combat. It closes by discussing the determinants of success in these engagements, and argues that only through an integrated understanding of battle dynamics at the two different levels can the clashes truly be understood. All naval battles were fought very close to land and might even involve land-based forces. The combat conditions of ancient sieges seem to have provided something of a dilemma for commanders in this period.