Rarely has the eldest child taken the throne. The introduction of artificial gestation under Sebastian I in the second millennium ISD and the institution of the palatine caste (and its commensurate life extension) in the early seventh millennium created a circumstance where the eldest child was of an age comparable to that of the reigning monarch. This change to basic human reproduction has led to the creation of a system of non-primogeniture, especially among the high houses, and especially in the Aventine House itself.

Born the 107th child of William XXIII Avent by his cousin and wife, Maria Agrippina, Princess of Shakespeare, Alexander was not the obvious choice for successor. A quiet, bookish child, he spent the first twenty-or-so years of his life at Caliburn House upon Avalon, where he spent his days studying in the gardens beneath the branches of the Tree of Gold. Even as a boy, Alexander frequented the Cenotaph of the God Emperor, being consumed by the legend of his sainted ancestor. He was also a great admirer of Hadrian Marlowe—already legendary at that point for his victories at Cellas, Oxiana, Thagura, and in the Battle Upon Demiurge, wherein he earned the name of Halfmortal.

At around twenty, the young Alexander was transferred from Avalon to Forum. A child of the Cielcin Wars, Alexander never knew peacetime, and grew up in the political and religious firestorm of the court-at-war. A devout follower of the Cult of Earth, Alexander expected to perhaps enter clerical life in adulthood—though his heart was with the Legions. It was perhaps for this piety he was chosen—unbeknown to him—to succeed his father. Though the process of heir selection in the latter Imperium might be dubbed aristogeniture (that is, succession by the best), in practice, the heir is selected…not quite at random, but with an eye toward grooming the prince or princess in question to be the ideal successor. It is for this reason he was likely attached to Hadrian Marlowe as his squire for the Nemavand expedition—though it is widely believed that the young Alexander lobbied for the appointment himself, out of his boyish admiration for the figure of Lord Marlowe.

Much has been made of the deterioration of the prince’s affections in the years that followed. Marlowe himself credits the Prince with more than one attempt on his life. Lord Marlowe attributes this enmity to his own failures as a teacher, his frustrations with a young man so like himself. Other accounts say the young Alexander simply feared Lord Marlowe’s growing popularity, and resented the betrothal of his favorite sister, Selene, to his former mentor.

Whatever the reason, there is one fact beyond dispute: it was Alexander who ordered the Sun Eater’s execution at the Tower of Morne.