structural:reformatting
Second and Third Philippics (344–341 BC)

In 344 BC Demosthenes travelled to the Peloponnese, to detach as many cities as possible from Macedon's influence, but his efforts were generally unsuccessful. Most of the Peloponnesians saw Philip as the guarantor of their freedom and sent a joint embassy to Athens to express their grievances against Demosthenes' activities. In response, Demosthenes delivered the Second Philippic, a vehement attack against Philip. In 343 BC Demosthenes delivered On the False Embassy against Aeschines, who was facing a charge of high treason. Nonetheless, Aeschines was acquitted by the narrow margin of thirty votes by a jury which may have numbered as many as 1,501.

In 343 BC, Macedonian forces were conducting campaigns in Epirus and, in 342 BC, Philip campaigned in Thrace. He also negotiated with the Athenians an amendment to the Peace of Philocrates. When the Macedonian army approached Chersonese (now known as the Gallipoli Peninsula), an Athenian general named Diopeithes ravaged the maritime district of Thrace, thereby inciting Philip's rage. Because of this turbulence, the Athenian Assembly convened. Demosthenes delivered On the Chersonese and convinced the Athenians not to recall Diopeithes. Also in 342 BC, he delivered the Third Philippic, which is considered to be the best of his political orations. Using all the power of his eloquence, he demanded resolute action against Philip and called for a burst of energy from the Athenian people. He told them that it would be "better to die a thousand times than pay court to Philip". Demosthenes now dominated Athenian politics and was able to considerably weaken the pro-Macedonian faction of Aeschines.