practising justice, of having nearly the same manners and customs as the Greeks, and they notice their hospitality to Grecian strangers.[13] Their war with the Etruscans in North Italy completed the ruin of an hereditary enemy of the Greeks,[14] and their war with the Illyrians no doubt largely strengthened the hands of Philip, the father of Alexander the Great, and enabled him to throw off the tribute which the Illyrians had imposed upon Macedonia. Nor did Alexander himself embark upon his expedition into Asia without having first assured himself of the friendship of the Celts. He received their ambassadors with cordiality, called them his friends, and received from them a promise of alliance. "If we fulfil not our engagement," said they, "may the sky falling upon us crush us, may the earth opening swallow us up, may the sea overflowing its borders drown us," and we may well believe that these were the very words used by the Celtic chieftains when we find in an Irish saga committed to writing about the seventh century[15] the Ulster heroes swearing to their king when he wished to leave his wing of the battle to repel the attacks of a rival, and saying, "heaven is over us and earth is under us and sea is round about us, and unless the firmament fall with its star-showers upon the face of the earth, or unless the earth be destroyed by earthquake, or unless the ridgy, blue-bordered sea come over the expanse (?) of life, we shall not give one inch of ground." While the ambassadors were drinking the young king asked them what was the thing they most feared, thinking, says the historian, that they would say himself, but their answer was quite different. "We fear no one," they said; "there is only one thing that we fear, which is, that the heavens may fall upon us; but the friendship of such a man as you we value more than everything," whereat the king, no doubt considerably astonished, remarked in a low voice to his courtiers what a vainglorious people these Celts were.[16] All through the life of Alexander the Celts and Macedonians continued on good terms, and amongst the many envoys who came to Babylon to salute the youthful conqueror of Persia, appeared their representatives also. Some forty years later, however, this good understanding came to an end, and the Celts overthrew and slew in battle the Macedonian ruler Ptolemy Keraunos about 280 B.C.