Thucydides called Acharnae the greatest of the Attic demes, and the numbers back him up. In the fourth century BCE, twenty-two of the five hundred members of the Athenian council were drawn from Acharnae alone, more than any other district could claim. That was real political weight in a democracy that ran on representation. The men who came down from the slopes north of the city were not a rustic afterthought. They voted, they served, they filled the assembly. Pindar singled them out for bravery. Where the name itself came from is older and stranger: probably pre-Greek, like so many Attic place-names, though ancient writers preferred to imagine the plain shaped like a fish, or to credit a forgotten hero named Acharnas.

Everything turned on the woods of Parnes. The Acharnians grew cereals, grapes, and olives like everyone else in Attica, but their signature trade was charcoal, slow-burned from the mountain's timber in earth-covered mounds that smoldered for days. The work was filthy and the workers were famous for it. Aristophanes built an entire chorus from them, men whose hearts, he joked, were as hard as the oak they charred. Even the local donkeys earned a reputation for unusual size, and at least one Acharnian, the oligarch Peisander, carried the nickname 'pack-donkey' for the rest of his career. This was a place that lent itself to caricature, and the comic poets took full advantage.

The smoke that defined Acharnae also drew an army. Early in the Peloponnesian War, the Spartans marched into the deme, torched its forests, and pitched camp in its fields, trying to goad the Athenians sheltering behind their walls into a pitched battle they were sure to lose. The temple of Ares, an important sanctuary here, was abandoned in the ruin. The Acharnians never forgot it. That bitterness hardened their reputation as fighters, the warlike streak Aristophanes plays on. Years later, in the chaos after Athens fell, the democratic exile Thrasybulus fought the Spartan-backed Thirty Tyrants in this same country, cutting their supply lines with a force of barely seven hundred men and two cavalry squadrons, and won.

People have lived on this ground since the Neolithic without a real break. Near the neighborhood of Lykopetra archaeologists found a Mycenaean tholos tomb, a beehive-shaped vault of the Bronze Age, and the scattered tombs across the area hint that Acharnae may once have been its own small power before Athens absorbed it. Most of what survives, though, dates from the classical and Hellenistic centuries: graveyards, stretches of the old road network, fragments of fourth-century BCE waterworks. A temple to Ares associated with the Acharnae region was eventually dismantled and rebuilt in the Athenian Agora during the reign of Augustus — though recent scholarship suggests it may have originated from nearby Pallene rather than Acharnae itself, a reminder that the ancient town's boundaries and influence spread across the plain. Today more than a hundred thousand people live in modern Acharnes, walking streets laid over the charcoal-burners' plain.