Galadriel the Lady of Lórien, the Lady of the Galadhrim, the Lady of Light, or the Lady of the Golden Wood

Stories of Galadriel's life prior to The Lord of the Rings appear in both The Silmarillion and Unfinished Tales. Galadriel was the only daughter and youngest child of Finarfin, prince of the Noldor, and of Eärwen, who was cousin to Lúthien. Her elder brothers were Finrod Felagund, Angrod, and Aegnor. She was born in Valinor during the Years of the Trees.

Galadriel is described as having been "blessed with the ability to peer into the minds of others and she judged them so fairly. But in Fëanor, she only sees darkness". As one of the members of the royal house of Finwë and having the blood of the Vanyar from her paternal grandmother, Indis, she was often called the fairest of all Elves, either in Aman or Middle-earth.

According to the older account of her story, sketched by Tolkien in The Road Goes Ever On and used in The Silmarillion, Galadriel was an eager participant and leader in the rebellion of the Noldor and their flight from Valinor; in fact, she was the "only female to stand tall in those days". She had however long since parted ways with Fëanor and his sons, and did not participate in the Kinslaying at Alqualondë. In Beleriand she lived with her brother Finrod Felagund at Nargothrond and at the court of Thingol and Melian inDoriath. In this account she met Celeborn, a kinsman of Thingol, in Doriath.

After the War of Wrath, the Valar prohibited the leaders of the Exiles from returning to the Undying Lands, so as one of those leaders Galadriel remained an Exile in Middle-earth. At the end of the Third Age, when she refused the One Ring, she was finally allowed to return to Valinor.

Unfinished Tales gathers many other accounts of Galadriel and Celeborn. One of these highlights a second version of how Galadriel came to Middle-earth. She lived with her mother's kindred in the Telerin port of Alqualondë and there met Celeborn, who would become her husband and co-ruler. Celeborn, by this account, was Olwë's grandson. Galadriel and Celeborn sailed from the West and came to Beleriand separately from the two main hosts of the Noldor (one that Fëanor led in the ships of the Teleri, the other led by Fingolfin and Finrod that crossed the Helcaraxë). Galadriel was thus not directly involved in the revolt of the Noldorin princes in this version, and indeed fought against them at Alqualondë during the kinslaying; but she fell under the Ban of the Valar because she left the Undying Lands without permission. In Beleriand she and Celeborn were welcomed by Thingol and lived in Doriath. When the Noldor arrived in Beleriand, Galadriel re-established contact with her brothers. In this version of the story, she is offered a pardon by the Valar, but refused it out of pride and therefore remained under the Ban. In even later accounts from Unfinished Tales, written not long before Tolkien died, Galadriel was not even subject to the Ban, and remained in Middle-earth of her own volition.

In both versions Celeborn and Galadriel play no important role in the Battles of Beleriand, as they judge the War of the Jewels to be hopeless against Morgoth's strength. Little is told of their subsequent activities in the First Age, and they leave Beleriand before the War of Wrath.

Second Age
They travelled first to Lindon, where they ruled over a group of Elves, probably as a fiefdom under Gil-galad who was the last High King of the Noldor. According to Concerning Galadriel and Celeborn, they then removed to the shores of Lake Nenuial (Evendim), and were accounted the Lord and Lady of all the Elves of Eriador.

Later, around SA 700, they moved eastward and established (or were welcomed into) the realm of Eregion or Hollin. At this time they made contact with a Nandorin settlement in the valley of the Anduin, which later became Lothlórien. At some point Celeborn and Galadriel left Eregion (where Celebrimbor either had been or now became the ruler) and settled in Lothlórien. According to some accounts, they became rulers of Lothlórien for a time during the Second Age; but in all accounts they would return to Lórien to take up its rule after Amroth was lost in the middle of the Third Age.

Early in the Second Age, the Númenórean King Tar-Aldarion presented some Mallorn seeds to Gil-galad, High-King of the Noldor in Middle-earth, ruler of the Kingdom of Lindon, the westernmost realm in Middle-earth; but these did not take root in his kingdom, so Gil-galad gave them instead to Galadriel. "Under her power" the mellyrn had sprouted in the land of Lothlórien, but "they did not reach the height or girth of the groves of Númenor."

Celeborn and Galadriel had a daughter, Celebrían, who later married Elrond Half-elven of Rivendell, thus making Galadriel and her husband Celeborn the grandparents of the twins Elladan and Elrohir and their younger sister Arwen Undómiel, future Queen of the Reunited Kingdom of Gondor and Arnor.

During the Second Age, when the Rings of Power were forged, Galadriel distrusted Annatar, the loremaster who taught the craft of the Rings to Celebrimbor and the other Noldor of Eregion. According to some accounts, Celebrimbor rebelled against her view and seized power in Eregion, so Galadriel departed to Lórien via the gates of Moria, though Celeborn stayed behind as he refused to enter the dwarves' stronghold. Her distrust was justified, for Annatar was revealed as Sauron pretending to be an emissary from the Vala Aulë. When Sauron attacked Eregion, Celebrimbor entrusted Galadriel with one of the Three Rings of the Elves, Nenya, the Ring of Water or the Ring of Adamant. Celeborn joined up with Elrond, whose force was unable to relieve Eregion but managed to escape back to Imladris. Celeborn was reunited with Galadriel after the war ended; according to one text, after some years in Imladris (during which Elrond first saw and fell in love with Celebrían) Galadriel's sea-longing became so strong that the couple removed to Belfalas and lived at the place later called Dol Amroth.

With the fall of Gil-galad in the War of the Last Alliance, Galadriel, Elrond, and Círdan became the most prominent of the rulers among the elves in Middle-earth, and Galadriel the foremost of the remaining Exiles.