The Lords of Andúnië were a group of royal Númenóreans descended from Elros through Silmarien, the daughter of the fourth of the Kings of Númenor, Tar-Elendil.

Silmarien was Tar-Elendil's eldest child and daughter. She did not ascend to the throne upon the death of her father, since the laws of Númenor at that time allowed only for the eldest son of the king to take the Sceptre of Númenor.

The Lords of Andúnië lived on the west coast of Númenor in the area of Andustar. It was they who welcomed the Eldar and remained faithful to the Valar after the shadow began to fall upon them.

The Lords of Andúnië led the people called the Faithful as they went against the teachings of the later Kings of Númenor and the King's Men.

The Faithful escaped the Downfall of Númenor and were cast across the sea and finally landed upon Middle-earth. There they were led by Elendil and his sons, Isildur and Anárion who were of the house of the Lords of Andúnië.
Encyclopedia entry originally written by Nienna-of-the-Valar