Herodotus Explains the Sack of Troy via Egypt

 Proteus (the pharoah of Egypt) began to ask Paris who he was and from whence he was voyaging; and he both recounted to him his descent and told him the name of his native land, and moreover related of his voyage, from whence he was sailing. After this Proteus asked him whence he had taken Helen; and when Paris went astray in his account and did not speak the truth, those who had become suppliants convicted him of falsehood, relating in full the whole tale of the wrong done. At length Proteus declared to them this sentence, saying, "Were it not that I count it a matter of great moment not to slay any of those strangers who being driven from their course by winds have come to my land hitherto, I should have taken vengeance on thee on behalf of the man of Hellas, seeing that thou, most base of men, having received from him hospitality, didst work against him a most impious deed. For thou didst go in to the wife of thine own host; and even this was not enough for thee, but thou didst stir her up with desire and hast gone away with her like a thief. Moreover not even this by itself was enough for thee, but thou art come hither with plunder taken from the house of thy host. Now therefore depart, seeing that I have counted it of great moment not to be a slayer of strangers. This woman indeed and the wealth which thou hast I will not allow thee to carry away, but I shall keep them safe for the Hellene who was thy host, until he come himself and desire to carry them off to his home; to thyself however and thy fellow-voyagers I proclaim that ye depart from your anchoring within three days and go from my land to some other; and if not, that ye will be dealt with as enemies."

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Let us now leave Homer and the "Cyprian Epic"; but this I will say, namely that I asked the priests whether it is but an idle tale which the Hellenes tell of that which they say happened about Ilion; and they answered me thus, saying that they had their knowledge by inquiries from Menelaos himself. After the rape of Helen there came indeed, they said, to the Teucrian land a large army of Hellenes to help Menelaos; and when the army had come out of the ships to land and had pitched its camp there, they sent messengers to Ilion, with whom went also Menelaos himself; and when these entered within the wall they demanded back Helen and the wealth which Paris had stolen from Menelaos and had taken away; and moreover they demanded satisfaction for the wrongs done: and the Teucrians told the same tale then and afterwards, both with oath and without oath, namely that in deed and in truth they had not Helen nor the wealth for which demand was made, but that both were in Egypt; and that they could not justly be compelled to give satisfaction for that which Proteus the king of Egypt had. The Hellenes however thought that they were being mocked by them and besieged the city, until at last they took it; and when they had taken the wall and did not find Helen, but heard the same tale as before, then they believed the former tale and sent Menelaos himself to Proteus. 

Source: http://www.gutenberg.org/files/2131/2131-h/2131-h.htm

Here is the question of justice, then. A whole empire comes to your doorstep, banging their shields with swords, burning your fields and howling that their brutal king has been wronged. Do you turn over a single woman to them, who wishes not to go but to remain with you?

I quite prefer the version of Homer. This is the glory of Troy: she came to the king for protection and he accepted her, and fought for her until nothing was left. How much better is that than a misunderstanding that seems as much an excuse to burn the wealthy city beyond just the pursuit of Helen? It was always an excuse, but were she in Egypt all along, what then?