Demosthenes (the orator) was born in Paeania, in Attica, around 384 BC. His father died when Demosthenes was seven years old. Demosthenes was left in the care of guardians, who squandered his estate. At the age of 20 Demosthenes prosecuted one of his guardians. His success in this contributed to his decision to enter into public life.

But Demosthenes had to overcome many disadvantages to become a great orator. Famously, he is said to have practised speaking with pebbles in his mouth, to overcome his stammer. Also, he is said to have recited verse as he ran uphill, to strengthen his voice, and to declaim on the sea-shore, to accustom himself to a noisy environment. He was given instruction by the actor Satyrus.

Demosthenes soon began to acquire reputation and influence. He used his position to appeal to his countrymen to unite against Philip of Macedon, in the powerful orations known as the "Philippics". His warnings, however, went unheeded. The final victory of the Macedonians over the Greeks was the battle of Chaeronea in 338 BC.

At this time Aeschines accused Ctesiphon (though the true target was Demosthenes). The trial was delayed until 330. At this trial, Demosthenes delivered the oration "On the Crown", considered his greatest (if not the greatest). Aeschines was defeated and left Athens, never to return.

In 324 Demosthenes was imprisoned on a trumped-up charge. He escaped, and lived in exile until the death of Alexander the Great in 323. Demosthenes returned and the Greek states rose against Macedonia, but were crushed. Demosthenes fled, but was pursued by the emissaries of Antipater. He took poison to avoid capture. He died in 322 BC.