List of Roman and Byzantine empresses

The term Roman empress usually refers to the consorts of the Roman emperors, the rulers of the Roman Empire. The duties, power and influence of empresses varied depending on the time period, contemporary politics and the personalities of their husband and themselves. Empresses were typically highly regarded and respected, and many wielded great influence over imperial affairs. Several empresses served as regents on behalf of their husbands or sons and a handful ruled as empresses regnant, governing in their own right without a husband.

Given that there were sometimes more than one concurrent Roman emperor, there were also sometimes two or more concurrent Roman empresses. For most of the period from 286 to 480, the Roman Empire, though remaining a single polity, was administratively divided into the Western Roman Empire and the Eastern Roman Empire. Through most of this period, the separated imperial courts had their own lines of succession, and as a result their own sequences of concurrent Roman empresses. The western empire fell in the late 5th century, its final empress being the wife of Emperor Julius Nepos. The eastern empire, often referred to as the 'Byzantine Empire' by modern historians, endured for almost another millennium until its fall through the fall of Constantinople in 1453. The final empress of the east, and final Roman empress overall, was Maria of Trebizond, wife of Emperor John VIII Palaiologos.

Though the constitutional power of empresses was never defined, it was generally accepted that their coronation, performed after that of their husbands, granted them some imperial power. Often, their primary duties were to oversee the organization of ceremonies at the imperial court as well as to partake in imperial and religious affairs. Although governmental power was most often vested only in the emperor, empresses could gain significant authority as regents for young children or when their husbands were absent. Though they were bound by the wishes and temperaments of their husbands, empress consorts could at times also effectively become influential co-regents. In some cases, emperors reinforced their legitimacy through marrying the daughter of a previous emperor. In such cases, empresses sometimes stressed their dynastic legitimacy, greater than that of their husbands, to achieve great influence. Several influential consorts, such as Theodora, wife of Justinian I, and Euphrosyne, wife of Alexios III, held their own courts. Theodora and Euphrosyne, during their husbands' reigns, established a parallel court alongside the imperial court—a separate palace with their own staff, royal attendants, and imperial guard, with their own imperial seal. State affairs were reported to them, and decrees issued by them carried the same weight as those of the emperor. Additionally, empresses, Irene of Montferrat, wife of emperor Andronikos II Palaiologos, and Anna of Savoy, wife of emperor Andronikos III Palaiologos and mother of emperor John V Palaiologos, left Constantinople for Thessalonica and established their own courts, ruling independently in that province. Irene did so following a disagreement with her husband over succession, while Anna, after losing in the Second Civil War (1341–1347), establishing her own court in Thessalonica and acting independently.

Titles

There was no single official term for the position of "empress" in Ancient Rome.

Common titles

• The Latin title augusta (Greek: αὐγούστα, augoústa), the female form of augustus, was usually given to Roman consorts. Insofar as augustus is understood as meaning "emperor", then a given woman could not become "empress" until being named augusta. However, not all consorts were given the title by their husbands. The title was sometimes given to other female members of the family, so empress and augusta are not always treated as synonyms. In the third century, empresses could also receive various honorific titles, such as māter castrōrum "mother of the castra" and māter patriae "mother of the fatherland".
• The Greek title basilissa (βασίλισσα), the female form of basileus, was a common title for Byzantine empresses. Empress regnant Irene sometimes adopted the male title basileus.
• The title despoina (δέσποινα), the female form of despotes, was also a common title for empresses in the later eastern empire.

Noncommon titles

• The title caesarissa (Greek: καισάρισσα, kaisarissa), the female form of caesar, was used for Ino Anastasia, etc. It was used by the consorts of emperors as caesars wife until being named augusta.
• The Latin term imperatrix, the feminine form of imperator, was used for Pulcheria, etc. It seems to have rarely been used for Roman empresses.
• The title autokratorissa (), the female form of autokrator, was used for Anna of Savoy, etc. It was not a common title for Roman empresses. Empresses regnant Zoe and Theodora sometimes adopted the male title autokrator.
• The title sebaste, the feminine form of sebastos, was used for Maria Skleraina, etc. It was the Greek translation of augusta and ranked as a quasi-empress.

All empresses of this period received the title augusta.

All empresses of this period received the title augusta.

All empresses of this period were named augusta on or shortly after their marriage.

All empresses during this period received the title augusta, with the sole exception of Numerian's wife.

Only Valeria received the title of augusta during the Tetrarchy, and only a few women did so in the Constantinian and Valentinianic dynasties.

All empress, with the exceptions of Galla, "Elen", and Thermantia, received the title augusta.

During the later 'Byzantine' period, all empresses (unless noted) received the title augusta; whether it was still considered a formal title or just a synonym to "empress" is not known.