Maglor was the second son of Fëanor and Nerdanel, and he inherited more of his mother's gentle spirit than any of his brothers. His name meant "cleaver of gold" and he was famed as a poet, bard, and singer. However, he did take the Oath of Fëanor in Tirion, and he shared in the woes that came of it. Maglor followed his father into exile, and saw him perish at the hands of the Balrogs.

With the rest of his brothers, he dwelt in the east of Beleriand, and he settled between the Little Gelion and the Greater Gelion, the two rivers that came together to form the Gelion itself. That region - which came to be known as Maglor's Gap - lacked hills or mountains, and was the place on Beleriand's border that was most open to attack from the north.

Maglor guarded this Gap for four and a half centuries, but it was eventually overcome in the Dagor Bragollach. The dragon Glaurung ruined Maglor's land, so that he was forced to flee to the fortress of his brother Maedhros on the hill of Himring to the west.

Sixteen years later, he marched out with Maedhros to the Nirnaeth Arnoediad. The elves were brought to ruin by the treachery of Uldor the Accursed. Maglor slew the Easterling, but the battle was lost. Maglor was wounded but managed to escape alive.

When the Fëanorians attacked the people of Eärendil and Elwing to try and reclaim one of the Silmarils, Maglor took care of the infants Elrond and Elros after their mother fled the attackers.

After the War of Wrath, the Silmarils were in the possession of Eonwë, herald of Manwë, who told the two remaining brothers that their right to possess the jewels had perished through the undeeds of their family, the three kinslayings comitted against the Teleri.

While Maglor was tempted to forsake his oath, Maedhros eventually persuaded him to come to Eonwë's camp and steal the Silmarils.They sneaked into the camp and managed to obtain the jewels. Eonwë saw them do it, but forbade others to slay them. However, the Silmarils burned in their hands and Maglor threw his in the sea. Maedhros jumped into a fiery chasm with his Silmaril.

Maglor was struck with guilt and from then on walked along the shore singing songs about the doom of the Noldor. He wrote Noldolante on that subject. His final fate is not known. It was said that he still walked along the shore singing. What is certain is that he came never back among the people of the Elves.

In the notes for a planned “excursus” on the names of the Sons of Fëanor (c.1968) Tolkien gave his Quenya name as Kanafinwë ‘strong-voiced’ or ‘commanding' In these same notes his mother-name is given as Makalaurë ‘forging gold’ thought to be a reference to the sound of his harping and singing. The element ‘laurë’ was used for golden light but never for the metal. (Source: HoME Vol.XII, The Shibboleth of Fëanor)