216 BC

Battle of Cannae

Hannibal destroys a Roman field army at Cannae

The Roman infantry drove into Hannibal's projecting centre; as it yielded, troops on the sides turned against them.

A crescent that folded inward

On the traditional Roman-calendar date of 2 August 216 BCE, beside the Aufidus River near Cannae in Apulia, Hannibal met the combined consular army of Gaius Terentius Varro and Lucius Aemilius Paullus. Hannibal had seized the Cannae citadel and the supplies stored there, and the Senate had directed the consuls to give battle.

The Roman infantry advanced tightly into Hannibal's deliberately projecting centre and pushed it back. As that centre yielded, Libyan infantry posted on its sides turned against the Roman flanks.

Hasdrubal's cavalry beat the Roman horse near the river, rode round behind the Roman formation and struck the compressed legionaries from the rear. Paullus was killed; Varro escaped to Venusia.

2 August, on which calendar?

2 August 216 BCE is the traditional date. It is a Roman-calendar date, and the Republican calendar did not map cleanly onto the later Julian one.

In solar terms the fighting may therefore correspond roughly to early July, which is why the day is best labelled traditional rather than fixed.

Numbers the ancient writers could not agree on

Polybius reports about 80,000 Roman infantry and slightly more than 6,000 cavalry against no more than 40,000 infantry and 10,000 cavalry, and puts the Roman dead at 70,000 — an ancient figure that remains disputed. Livy's totals differ, and the ancient accounts disagree on deaths, captures and escapes.

The often-quoted total of 86,000 Romans also obscures that 10,000 infantry were assigned to guard the camp; Polybius counts them separately as prisoners. Michael Fronda's modern summary gives at least 50,000 Roman and allied dead.

In Rome the Senate appointed a dictator, raised emergency levies, armed 8,000 willing slaves rather than ransom captured citizens, and refused to negotiate peace.

Sources

Researched 23 Aug 2026 5 sources 2 audit passes Traditional date

How this was checked

Researched from the web into a fact sheet, rewritten from that sheet, then audited against it by a different model. How the pipeline works →

Traditional date. Conventionally dated here; the research places it at -216-08-02.

What the sources leave uncertain

2 August is the traditional Roman-calendar date. Because the Republican calendar did not map cleanly onto the later Julian calendar, it may correspond roughly to early July in solar terms.
Livy and Polybius give different totals for strength, deaths, captures and escapes. All exact casualty figures should be labeled as source-reported estimates.
The hostile portrayal of Varro and the tidy contrast between a rash Varro and prudent Paullus may reflect aristocratic source traditions; Polybius was patronized by Paullus's descendants.