Timotheus, upon his acquittal of a charge of negligence in 373 BCE, had served the king of Persia as a mercenary, and is now back in the service of Athens.

He overruns Samos after a ten-month siege in 366-365 BCE, and installs an Athenian cleruchy on Samos, a capital error.

Timotheus' action can be technically justified: Samos is not a member of the Athenian Confederacy, and Persia had violated the King's Peace by installing its garrison; thus the cleruchy can be seen as a military response to Persian provocation in an area not covered by the rules of the charter of 377 BCE.

Its effect on Greek opinion is damaging nonetheless, and …

…the Thebans quickly try to exploit it.

Timotheus goes on to capture a number of cities in the northern Aegean, but fails in two seaborne attempts to take Amphipolis.

Dionysius II of Syracuse sends help to Sparta, enabling it to recover control over some formerly subject communities in 365, but that is about the limit of his interference in mainland Greek affairs.

Perdiccas kills Ptolemy in 365 BCE and assumes control of Macedon’s government.

Of the reign of Perdiccas we have very little information, knowing only that he was at one time engaged in hostilities with Athens on account of Amphipolis, and that he was distinguished for his patronage of men of letters.

Among these, we are told that Euphraeus, a disciple of Plato, rose to so high a place in his favor as completely to govern the young king, and exclude from his society all but philosophers and geometers.

He also served as Theorodokos (sacred envoy-receivers, whose duty is to host and assist the Theoroi, or "viewers" before Panhellenic Games and Festivals) in the Epidaurian Panhellenic games of about 365 BCE.

Iphicrates, like Timotheus, fails in attempts from 367 BCE to 364 BCE to recover Amphipolis.

The Arcadian army, after ravaging Elis in the spring of 364 BCE, marches against the little town Cromnus, in the neighborhood of Megalopolis, and lays siege to the city, in which Archidamus had left a small garrison.

The Arcadians defeat Archidamus's relief force.

The Boeotian league destroys Thebes' Boeotian rival Orchomenus in 364 BCE.

Epaminondas in this year commands a fleet against the Athenian navy and …

…Pelopidas marches against Alexander of Pherae, who, during the past three years, has seemed to renew his attempts to subdue the states of Thessaly, especially Magnesia and Phthiotis, for upon the expiry of the truce in 364 BCE they again apply to Thebes for protection from him.

The Theban army under Pelopidas is said to have been dismayed by an eclipse on July 13, 364, and Pelopidas, leaving the bulk of his army behind, enters Thessaly at the head of three hundred volunteer horsemen and some mercenaries.

At Cynoscephalae (Greek: “Dogs' Heads”), an ancient range of hills in Thessaly, the Thebans defeat Alexander, but Pelopidas is killed.

This is closely followed by another Theban victory under Malcites and Diogiton.

Alexander is now forced to restore the conquered towns to the Thessalians, confine himself to Pherae, join the Boeotian League, and become a dependent ally of Thebes.

The Thebans release the hostage prince Philip in 364 BCE also.

The Macedonian prince during his captivity has received a military and diplomatic education from Epaminondas, become the eromenos of Pelopidas, and lived with Pammenes, an enthusiastic advocate of the Sacred Band of Thebes.

The skills and techniques thus acquired are soon to prove valuable.

Amyntas, after a turbulent five-year interval of two brief reigns, those of Alexander II and Ptolemy, and one intervention by a pretender, Pausanias, had in 365 BCE been succeeded by Perdiccas, the second of his sons by Eurydice.

When Philip returns to Macedonia, his brother Perdiccas soon finds him ready for a command.

The fourth century Macedonian kings make grants of land in exchange for military service (a system hinted at by literary sources and illustrated by inscriptions).

Given the size and fertility of the areas controlled by the Macedonian kings, there is huge potential for military achievement, provided Macedon's chronic enemies and invaders can be appeased or crushed.