Agamemnon, the son, or, according to a less common account (for which see Schol. ad Iliad II. 249), the grandson of Atreus, being {40} distinguished above the other Hellenic princes for wealth and power, was either by special election appointed, or by that sort of irregular kingship common among half-civilized nations, allowed to conduct the famous expedition against Troy that in early times foreshadowed the conquests of Alexander the Great, and the influence of the Greek language and letters in the East. Such a distant expedition as this, like the crusades in the middle ages, was not only a natural living Epos in itself, but would necessarily give rise to that intense glow of popular sympathy, and that excited state of the popular imagination, which enable the wandering poets of the people to make the best poetic use of the various dramatic incidents that the realities of a highly potentiated history present. Accordingly we find, in the very outset of the expedition, the fleet, storm-bound in the harbour of Aulis, opposite Eubœa, enabled to pursue its course, under good omens, only by the sacrifice of the fairest daughter of the chief. This event--a sad memorial of the barbarous practice of human sacrifice, even among the polished Greeks--formed the subject of a special play, perhaps a trilogic series of plays,[f4] by Æschylus. This performance, however, has been unfortunately lost; and we can only imagine what it may have been by the description in the opening chorus of the present play, and by the beautiful, though certainly far from Æschylean, tragedy of Euripides. For our present purpose, it is sufficient to note that, in the Agamemnon, special reference is made to the sacrifice of Iphigenia, both as an unrighteous deed on the part of the father, for which some retribution was naturally to be expected, and as the origin of a special grudge in the mind of the mother, which she afterwards gratifies by the murder of her husband.