Andreth was born in Ladros in Dorthonion. She was wise in thought and learned in the lore of Men and thus was called Saelind (Wise-heart) by the Elves of her time. In her earlier life she lived in the house of Belemir in Ladros, where she had learned the lore of the House of Marach from Adanel.
Andreth was deeply in love with Aegnor, son of Finarfin. The love was returned but never fulfilled, since Aegnor departed from motives of wisdom as he felt his coming death, thus they never married and had no children. She had a close friendship with Aegnor's brother Finrod Felagund, who often visited her during the Siege of Angband to converse and debate with her on the matters of Elves and Men. One such conversation was written down and later known as Athrabeth Finrod ah Andreth, where she and Finrod discussed differences between Elves and Men.
She probably died when Morgoth broke the Siege of Angband in the Dagor Bragollach in FA 455 of causes unknown. She was the only known person of Mankind to have had a romantic relationship with someone of Elvenkind before Beren.
The name Andreth was a Sindarin word that meant "patience". The first element of her name may have come from the word and, meaning "long", possibly alluding to a meaning such as "long lasting", although the second element reth is more difficult to decipher and appears to have no immediate explanation.
As said, Andreth was also known as Saelind, meaning "wise heart", which comes from the Sindarin words sael, meaning 'wise', and ind, meaning "inner thought" or "heart".
Saelon and Saelin were two names Tolkien came up with that preceded Saelind.
|Foreign Language||Translated name|
|Kazakh||Андретһ (Cyrillic) Andreth (Latin)|
|Serbian||Андрет (Cyrillic) Andret (Latin)|
|Uzbek||Андретҳ (Cyrillic) Andreth (Latin)|
- The History of Middle-earth, Vol. 12: The Peoples of Middle-earth, XVII: "Index"
- The History of Middle-earth, Vol. 10: Morgoth's Ring, Athrabeth Finrod ah Andreth
- The History of Middle-earth, Vol. 12: The Peoples of Middle-earth, XII: "The Problem of Ros", Notes
- The History of Middle-earth, Vol. 12: The Peoples of Middle-earth, XVI: "The New Shadow", Notes