Here is an excerpt:
The legend of Gil-galad and Elendil’s war against Sauron at the end of the Second Age of Middle-earth has been the subject of much research and speculation among Tolkien’s fans. As with all aspects of his mythology, the few mentions of this great struggle imply a depth which draws the imagination toward a fuller account which surely must have existed in the author’s mind, if not in any of his extant writings. Most of us are familiar with the outline of the war, and many can sketch out the events in a general progression from the first assault on Minas Ithil to the final combat on Orodruin.
Yet so many questions remain that one must wonder if Tolkien himself did not ask them of himself. Who were the great princes and captains the memory of whose banners made Elrond pause and sigh at his council an Age later? Where did these armies come from, and what were their reasons for joining the Alliance? If we do not know their numbers, do we know anything at all of their battle order and progressions?
Some of what follows is necessarily speculative. It cannot be otherwise for there are gaps in the record. Yet Tolkien sprinkled here and there pieces of information concerning this great war in which “all living things were divided…save the Elves only” (The Silmarillion, p. 294).
The final war of the Second Age brought together many peoples on both sides for a cataclysmic engagement which rivaled the great War of Wrath at the end of the First Age of the Sun. Although the Valar did not participate in this war, the conflict culminated a long and pendulous series of disputes between Sauron and the Elves and the Men of Númenor. The war represented Sauron’s last desperate grasp for power in Middle-earth in his ancient campaign to gain control over the Elves and Men.
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