An Athenian general incurs Philip's wrath in 341 BCE for operating too near one of his towns in the Chersonese.

Philip demands his recall, but Demosthenes replies in a speech, On the Chersonese, that the motive behind the Macedonian's “scheming and contriving” is to weaken the Athenians' will to oppose Philip's conquests.

“Philip is at war with us,” he declares, “and has broken the peace.” Shortly afterward, Demosthenes delivers his Third Philippic, perhaps the most successful single speech in his long campaign against Philip.

As a result, Demosthenes becomes controller of the navy and can thus carry out the naval reforms he had proposed in 354 BCE.

In addition, a grand alliance is formed against Philip, including Byzantium and former enemies of Athens, such as Thebes.

Indecisive warfare follows, with Athens strong at sea but Philip nearly irresistible on land.

The Macedonian army is well organized under a single brilliant commander who uses cavalry in coordination with highly disciplined infantry, while the Greek alliance depends upon what is essentially a group of citizens' militia.

Phocion again acquits himself brilliantly in the Athenians' second campaign against the Macedonians and their allies at Euboea in 341 BCE.

Sicyon is celebrated during the fourth century BCE for its school of painters and sculptors, including the master sculptor Lysippus.

Head of the school at Argos and Sicyon in the time of Philip of Macedon, he gains fame for the new and slender proportions of his figures and for their lifelike naturalism.

Originally a worker in bronze, he had taught himself the art of sculpture by studying nature and the Doryphorus (Spearbearer) of Polykleitos, whose canon of ideal male proportions he modifies by creating a smaller head and slimmer body that increases his figures' apparent height.

Lysippus' portraits of Philip's son Alexander are many; he sculpts Alexander from boyhood onward, and Alexander will have no other sculptor portray him.

Among the works attributed to him are the so-called Horses of Saint Mark, ...

According to Pliny, he produced more than fifteen hundred works, all of them in bronze.

Commentators noted his grace and elegance, and the symmetria or coherent balance of his figures, which were leaner than the ideal represented by Polykleitos and with proportionately smaller heads, giving them the impression of greater height.

He was famous for his attention to the details of eyelids and toenails.

His pupil, Chares of Lindos, will construct the Colossus of Rhodes, one of the Seven Wonders of the Ancient World.

As this statue does not exist today, debate continues as to whether its sections were cast in bronze or hammered of sheet bronze.

Renewed warfare in Sicily ends in about 341/340 BCE with the final defeat and execution of Hicetas.

A treaty is concluded confining the Carthaginians to the area west of the Halycus (Platani) River.

The Samnites gain several towns in southern Campania under the peace concluded with Rome in 341; this engenders great resentment among Rome’s Latin allies.

Most of the rest of Campania comes under Roman protection.

Artaxerxes, having rebuilt Persian power, combines forces with Phocion’s Athenian forces at Byzantium in 340—339 to oust Philip from Anatolia.

Philip's brother-in-law, King Alexander of Molossia (in Epirus, located in present Albania and northwestern Greece, with Illyria to the north, the Pindus mountains to the east, and the Gulf of Ambracia—near Préveza—to the south), around 340 unifies the Epirotes.