Argeleb II was the tenth King of Arthedain and a Dunadan.
When he was King, the plague came into Eriador from the Southeast. Cardolan was depopulated heavily, and the hobbits and all other people suffered greatly. The plague weakened as it came to Arthedain, and the country therefore wasn't affected as badly as the lands of Gondor and southern Eriador had been.
At this time the Dunedain dwindled in Cardolan, and evil spirits from Angmar entered the deserted graves in which many of the Dunedain's lords and kings were buried.
Argeleb II was the son of Araphor, and he was succeeded by his son, Arvegil.