Irene Breaks Imperial Precedent, Ruling Byzantium as “Basileus” in Historic 797 Decree

In the months after August 797, officials in Constantinople issued a routine legal ruling on inheritance. On the surface, it was the sort of administrative text that normally vanished into the empire’s paperwork. Yet its heading made it remarkable: the decree was promulgated in the name of the basileus—the standard masculine Greek title for a Roman emperor—and the person bearing that title was Irene. For the first time, a woman ruled the Roman Empire while styling herself with the full imperial designation.

Nothing in Irene’s early life suggested such an outcome. Born in Athens around 752, she came from the aristocratic Sarantapechos family, but her world was far from imperial. Athens was a modest town of only a few thousand people, isolated from the rhythms of the capital except for the limited contact brought by a ship that arrived just a handful of days each month. Constantinople, the nerve center of the Eastern Roman state, was not simply distant—it was another universe.

That distance collapsed for political reasons. Emperor Constantine V calculated that marrying his son, Leo IV, to Irene would help secure the backing of her relatives as he prepared a campaign aimed at restoring Roman authority in central Greece. The match pulled Irene abruptly into high politics. In early October 769, she left Greece for the capital, still a teenager, with her father already dead and accompanied primarily by female family members and attendants.

Her arrival, on 1 November, was staged to impress: she approached the city at the head of a flotilla of warships draped in silk. The metropolis she encountered would have been overwhelming even to seasoned travelers. Constantinople’s massive walls, the opulence of the imperial palace, and the soaring presence of Hagia Sophia—then the largest church in the world—were unlike anything she could have imagined in Athens.

There was little time to take it in. Almost immediately after disembarking, Irene was swept into a carefully orchestrated sequence of ceremonies: public welcomes, celebrations of her betrothal, her coronation as empress, and the formal rites of marriage. Receptions followed in which the empire’s governing class—magistrates, senators, administrators, and their spouses—paid homage, kneeling in deference.

For many young royals, the day would have blurred into a parade of names and faces. Irene, however, treated it as a political opportunity. She registered individuals amid the crowd and grasped what each might represent: a future patron, protector, or partner in a court where she began with few personal connections. From the outset, she set about cultivating a web of support among the powerful people she met.

Her standing strengthened decisively on 14 January 771 with the birth of her son, Constantine. He was proclaimed porphyrogenitus—“born in the purple”—a label reserved for an heir delivered in the palace’s purple chamber, both literally and symbolically marked as dynastic royalty. The child’s arrival had immediate consequences for the succession. When Constantine V died on 14 September 775, Leo IV faced rivals in the form of five ambitious half-brothers. But Leo’s claim was reinforced by the presence of a legitimate son to extend the imperial line.

Leo soon named the five-year-old Constantine as his heir and compelled his half-brothers to swear a public oath of loyalty to the boy. Within a year, those same half-brothers were exiled, accused of violating that pledge. Contemporary writers did not record what role Irene may have played in neutralizing them, but her influence was difficult to miss after Leo’s own reign ended suddenly.

On 8 September 780, Leo died following an infection of his hair follicles—reportedly brought on by prolonged use of a heavily jeweled crown. The throne passed formally to the nine-year-old Constantine VI. Yet Irene was positioned to exploit a central reality of imperial rule: a child emperor could not govern alone, and power in Constantinople belonged to whoever could command the court.

Why it matters

Irene’s ascent marks a turning point in Roman political history, revealing how court networks, dynastic legitimacy, and ceremonial authority could elevate an outsider—and even a woman using a masculine imperial title—to the highest office. Her story also underscores how succession crises could reshape governance when emperors died young or left underage heirs. What followed would affect not only the palace, but the empire’s religious and political direction for years to come.