For a little time Rome was at peace, and in 235 B.C. the gates of the temple of Janus were closed for the first time since the reign of the peace-loving King, Numa Pompilius. But ten years later, the Gauls once again threatened to invade Rome. They were always foes to be dreaded, and some of the old superstitious fears, which had apparently vanished for ever, began once more to spread among the Roman legions. Omens of ill too were rife. The Capitol was struck with lightning, so the Sibylline books were opened, and behold, it was written, ‘When the lightning shall strike the Capitol and the temple of Apollo, then, must thou, O Roman, beware of the Gauls.’ After that the simplest event seemed to the Romans to forebode evil. And while they brooded over the meaning of a strange light in the sky or a cloud of curious aspect, a large Gallic army was marching through Etruria, upon Clusium, a town only three days’ march from Rome. This was the very way their fathers had taken long years before. When the Consuls were absent from Rome, or already engaged with other matters, prætors were sent to lead the Romans against the foe. In this case it was a prætor who was sent with a reserve corps to track the enemy. He succeeded in following the Gauls to Clusium, and believed the enemy was in his grasp. But during the night, the main body of the Gauls slipped quietly out of their camp and marched some distance off, leaving only the cavalry to guard the tents. They hoped to entrap the Romans. The prætor, finding only a small force of cavalry in the camp, ordered an attack. As the Gallic horse retreated, the Romans followed, to find themselves, almost at once, face to face with the whole force of the barbarians. A fierce struggle followed, in which six thousand Romans were slain. Those who were left alive entrenched themselves with the prætor on a hill, and were at once surrounded by the Gauls. Meanwhile Æmilius, one of the Consuls, found himself free to hasten to Clusium with a large army. Here he heard of the disaster that had befallen the arms of Rome, and he resolved to restore her fortune. The prisoners on the hill were soon cheered to see the watchfires of their comrades, and they were sure that in the morning the Consul would scatter the barbarians. But the Gauls had no wish to encounter Æmilius while they were laden with prisoners and booty. So they began to march northward, followed by the Consul, who harassed their rear, and wrested what booty he could from the retreating-foe. Suddenly the barbarians were ordered to halt. Their chiefs had seen another army approaching. If they were Romans, the Gauls saw that they were caught in a trap. It was indeed a Roman army that was marching toward them, led by Regulus, the son of the Consul who had perished at Carthage. He was on his way to Rome when he unwittingly startled the Gauls by his appearance.