In these it is told how Nabonidus the king of Babylonia made a military campaign to northern Arabia in 552 BC or somewhat later, conquering Tayma, Dedan and Yathrib, the old Medina.
The Cylinders of Nabonidus refers to cuneiform inscriptions of king Nabonidus of Babylonia (556-539 BC).
As a work of historical fiction, this novel has several characters who were real or from ancient mythologies: Alexander the Great, Cyrus, Marduk, Nabonidus, Pharaoh.
In 539 BCE, Nabonidus retired to Tayma for worship and looking for prophecies, entrusting the kingship of Babylon to his son.
Howard also used the name of 'Nabonidus' (father of Belshazzar) in the Conan tale "Rogues in the House" which appeared in Marvel's Conan the Barbarian #11.
In contrast to the previous book by Raymond P. Dougherty, Beaulieu's book downplays the role of Nabonidus' heterodox religious beliefs in causing his split rule with his son Belshazzar, instead highlighting political and economic factors.
Around the same time, another Armenian by the name of Arakha, son of Haldita, claimed to be the son of the last king of Babylon, Nabonidus, and renamed himself Nebuchadnezzar IV.