Nabonidus (Nabû-na'id, 556–539 BCE), son of the Assyrian priestess Adda-Guppi,[1] came to the throne in 556 BCE, after overthrowing the young king Labashi-Marduk. For long periods he entrusted rule to his son, prince and coregent Belshazzar, who was a capable soldier, but a poor politician. All of this left him somewhat unpopular with many of his subjects, particularly the priesthood and the military class.[2] To the east, the Achaemenid Empire had been growing in strength.