Nirnaeth Arnoediad - the Battle of Unnumbered Tears - was the fifth and most disastrous of the Battles of Beleriand. It was fought on Anfauglith in the summer of FA 473 between the forces of Morgoth, led by Gothmog, Lord of Balrogs and Glaurung the Dragon, and the Union of Maedhros.

The Union of Maedhros was a military alliance formed to assail Morgoth. Because of the evil wrought by the Oath of Fëanor, many Eldar such as Orodreth of the Noldor of Nargothrond and Thingol of Doriath did not join the Union. However, enough of the Noldor of Hithlum and the Edain of the Third House joined to form two massive armies.

The campaign began when Morgoth marched against the western army of the Union commanded by Fingon. Gwindor of Nargothrond, enraged by the mutilation and murder of his brother Gelmir son of Guilin, broke the defensive alignment of Fingon at Eithel Sirion and, followed by most of the western army, drove the host of Morgoth back to the Gate of Angband in three days.

At this point, on the fourth day of the war, the Nirnaeth Arnoediad began. Morgoth released a huge army from hidden doors in Thangorodrim, and for two days Fingon was forced back with heavy losses. The rearguard, composed of an army of the Edain led by Haldir of the Haladin, was decimated, and by the second evening Fingon was surrounded by Orcs. After a night of bitter fighting, Fingon's company was reinforced by Turgon and ten thousand soldiers from Gondolin, who advanced from the Pass of Sirion.

Meanwhile, the eastern army of the Union, led by Maedhros, had been delayed by reports of treachery, but at last they arrived to attack the Orcs from the rear. However, Morgoth unleashed his Balrogs, wolves, and dragons on the right flank of Maedhros, and the two armies of the Union could not link up. The battle hung in the balance until the Easterlings of Ulfang, marching with Maedhros, went over to Morgoth's side and attacked the eastern Union force from the rear. Attacked from three sides and unable to withstand the dragons, Maedhros' forces broke, but the Dwarves of Belegost, let by Lord Azaghâl, stood firm against Glaurung and enabled an orderly retreat.

Maedhros thought he was leading his troops to victory but what they got was a massacre. Almost the whole of the Union was annihilated, and the Nirnaeth Arnoediad ended when Gothmog, Lord of Balrogs bound Húrin and took him off to Angband.
Encyclopedia entry originally written by Nénuwen