Ahura-Mazda?
Atossa was an Achaemenid ruler and daughter of Cyrus the Great and Cassandane. She lived from 550 BC to 475 BC and presumably was a sister of the Persian ruler Cambyses II. Atossa wedded Darius I amid 522 BC. Xerxes was the offspring of Darius I and Atossa. While Darius was planning for another war against Greece, a rebellion prodded in Egypt in 486 BCE because of substantial charges and the expulsion of experts to commence the manufacture of Persepolis. Under Persian law, the king was obliged to pick a successor before setting out on perilous undertakings. At the point when Darius chose to leave (487-486 BCE), Darius arranged his tomb at Naqsh-e Rustam (five kilometers from his regal castle at Persepolis) and delegated Xerxes, his eldest child by Atossa, as his successor. Be that as it may, Darius couldn't lead the battle because of his sudden death in October 486 BCE at 64 years old.
After this death Darius’s eldest son Artobazan had claimed ownership to the crown, but Xerxes used his bloodline to skip the que of his two elder brothers explaining he was son of Atossa, daughter of Cyrus the Great and that it was Cyrus who had won the Persians their freedom. This is shown and expressed by an inscription on a door jam at the palace of Persepolis “Xerxes, son of Darius, an Achaemenid”, Xerxes stating ‘An Achaemenid’ is done so with pride a proclamation on why he is more worth and divine and why he deserve kingship of his more commoner brothers. Xerxes was assigned beneficiary obvious by his father in inclination to his older sibling Artabazanes. A bas-relief on the southern colonnade of a patio in the treasury of Persepolis, and in addition the bas-reliefs on the east entryway of the tripylon (a decorative stairway) portray him as the beneficiary evident, remaining behind his father, who is situated on the throne. At the point when his dad passed on, in 486 bce, Xerxes was around 35 years of age and had represented Babylonia for a long time. This action of satrap is believed to be a hint that Xerxes was planned next of kin as he was undergoing a kind of political training to prepare him for a future as King of Persia, the next in the Achaemenid line of Kings.
In contrast to Xerxes coming to throne by the power of his bloodline, there is a theory that states that Xerxes was destine to power by the great Ahura-Mazda and it was his will that saw Xerxes be first born after Darius had secured right to the throne of Persia.
That the Xerxes mother and her link to Cyrus the Great was only an advantage in Ahura-Mazda's claim of Xerxes to be the divine ‘King of Kings’. Xerxes expresses this claim of divinity on a block of Limestone at persepolis “Saith Xerxes the king: had other sons of Darius there were, [but]... thus unto Ahura-Mazda was the desire, Darius my father made me the greatest after himself.” This is thus showing Xerxes grand claim that Ahura-Mazda himself gives the consent of Xerxes right, and it is something Xerxes repeats and repeats because as with every new King there is always the naysayers that believe against the new rule, so Xerxes took the god of Persian Empire and used him in propaganda to enforce his ruling because it would be spiritual suicide for them to dismiss the ruling of their own god. This propaganda of Xerxes claiming his divinity can be found on the the Old Persian text known from three slabs of stone from Persepolis and the citadel of Pasargadae stating “A great god is Ahuramazda, who created this earth, who created yonder sky, who created man, who created happiness for man, who made Xerxes king, one king of many, one lord of many.” Thus Xerxes is crushing any disbeliefs that he does not hold right to
the throne as he was personally chosen by Ahura-Mazda to be the overall ruler ‘King of Kings’.
In conclusion there is still much debate whether Xerxes was brought to prominence by the influence of his mother Atossa and the fact that she held direct blood link to Cyrus the Great the savior and builder of the Persian Empire or whether it was the will of Ahura-Mazda and the fact that by his will it would be Xerxes to be first born after Darius takes control of the throne. It is controversial but I believe that the evidence points more to the chance that Xerxes would be first born after Darius’s gain of power and thus being first born of royal blood he was the most likely candidate, but whether it was the will of Ahura-Mazda is open to religious beliefs. What is known and is for certain is that Xerxes would have his rise to prominence.