War was a major source of income for Hellenistic monarchs. A remarkable number of innovative military figures arose in Greece in the fourth century: Iphicrates and Chabrias of Athens, Epaminondas, Pelopidas and Pammenes of Thebes, Agesilaus of Sparta and Bolis of Crete, to name only a few. It was, however, Philip II of Macedon who drew many of the new elements of fourth-century warfare together, creating a formidable military machine. The Macedonian king fashioned a true combined arms force, streamlined the logistics of his army, and fashioned an up-to-date siege train. Perhaps most significantly, Philip wrought a new form of political organization, the Greek monarchy, able to direct this new military machine with a single will. Hellenistic strategic decisions were generally based on military circumstances and the desire to defeat the enemy and secure victory. Beginning with the Peloponnesian War and continuing into the fourth century, one sees Greek logistics improving significantly.