Juno (Hera), seeing things go thus prosperously for the Trojans, felt her old animosity revive, summoned Alecto from Erebus, and sent her to stir up discord. The Fury first took possession of the queen, Amata, and roused her to oppose in every way the new alliance. Alecto then speeded to the city of Turnus, and assuming the form of an old priestess, informed him of the arrival of the foreigners and of the attempts of their prince to rob him of his bride. Next she turned her attention to the camp of the Trojans. There she saw the boy Iulus and his companions amusing themselves with hunting. She sharpened the scent of the dogs, and led them to rouse up from the thicket a tame stag, the favourite of Silvia, the daughter of Tyrrheus, the king's herdsman. A javelin from the hand of Iulus wounded the animal, and he had only strength left to run homewards, and died at his mistress's feet. Her cries and tears roused her brothers and the herdsmen, and they, seizing whatever weapons came to hand, furiously assaulted the hunting party. These were protected by their friends, and the herdsmen were finally driven back with the loss of two of their number. These things were enough to rouse the storm of war, and the queen, Turnus, and the peasants all urged the old king to drive the strangers from the country. He resisted as long as he could, but, finding his opposition unavailing, finally gave way and  retreated to his retirement. 

OPENING THE GATES OF JANUS

It was the custom of the country, when war was to be undertaken, for the chief magistrate, clad in his robes of office, with solemn pomp to open the gates of the temple of Janus, which were kept shut as long as peace endured. His people now urged the old king to perform that solemn office, but he refused to do so. While they contested, Juno herself, descending from the skies, smote the doors with irresistible force, and burst them open. Immediately the whole country was in a flame. The people rushed from every side breathing nothing but war. Turnus was recognized by all as leader; others joined as allies, chief of whom was Mezentius, a brave and able soldier, but of detestable cruelty. He had been the chief of  one of the neighbouring cities, but his people drove him out. With him was joined his son Lausus, a generous youth, worthy of a better sire.