As to the Romans, they had robbed their neighbors already, and had no right to find fault.
This put the Fabian brothers in a rage, and they forgot the caution of their family, as well as those rules of all nations which forbid an ambassador to fight, and also forbid his person to be touched by the enemy; and when the men of Clusium made an attack on the Gauls they joined in the attack, and Quintus, the eldest brother, slew one of the chiefs.

Brennus, wild as he was, knew these laws of nations, and in great anger broke up his siege of Clusium, and, marching towards Rome, demanded that the Fabii should be given up to him.

Instead of this, the Romans made them all three military tribunes, and as the Gauls came nearer the whole army marched out to meet them in such haste that they did not wait to sacrifice to the gods nor consult the omens.

The tribunes were all young and hot-headed, and they despised the Gauls; so out they went to attack them on the banks of the Allia, only seven and a-half miles from Rome.

A most terrible defeat they had; many fell in the field, many were killed in the flight, others were drowned in trying to swim the Tiber, others scattered to Veii and the other cities, and a few, horror-stricken and wet through, rushed into Rome with the sad tidings.