Ashur-dan III was the son of Adad-nirari III, and succeeded his brother Shalmaneser IV in 773 BC. Ashur-dan's reign was a difficult age for the Assyrian monarchy. The rulership was severely limited by the influence of court dignitaries, particularly that of Shamshi-ilu, who was the commander-in-chief of the army (turtanu) at that time. According to the eponym canon, in 765 BC, Assyria was hit by a plague, and in the following year, the king could not campaign (it was customary for the Assyrian king to lead a military expedition every year). In 763 BC, a revolt broke out, which lasted until 759 BC, when another plague struck the land.
His reign and the reigns of preceding Assyrian kings have been astronomically dated based on the only verifiable reference to a solar eclipse in Assyrian chronicles, the eclipse of Bur Sagale.