Aldor

In J.R.R. Tolkien's Middle-earth legendarium, Aldor was the third King of Rohan, and its longest raining monarch.

Aldor was the second son of King Brego. His elder brother Baldor was lost while attempting to pass the Paths of the Dead, so Aldor became king when his father died, in T.A. 2570, at the age of 26.

His long rule was a golden age for Rohan, as the numbers of the Rohirrim increased, and the Dunlendings were chased past the Gap of Rohan beyond the borders of Adorn and Isen. He also established Dunharrow as a refuge.

Aldor had many children, of which the three eldest were daughters. He ruled for 75 years, and became known as Aldor the Old. He died in T.A. 2645, at the age of 102, a year after the birth of his first great-great-grandson. He was succeeded by his fourth child, Fréa, who had to wait until he was himself seventy-five years old before he became Lord of the Mark.

Reference

 * The Encyclopedia of Arda