Konstantinos IX Monomachos

Constantine IX Monomachos (Greek: Κωνσταντῖνος Μονομάχος, romanized: Kōnstantīnos Monomachos; c. 980/c. 1000

– 11 January 1055) reigned as Byzantine emperor from June 1042 to January 1055. A member of the urban aristocracy, Constantine became emperor through marriage to Augusta Zoë Porphyrogenita in 1042. The couple shared the throne with Zoë's sister Theodora Porphyrogenita. Constantine's energetic rule was one of the most consequential in the Byzantine Empire's tumultuous 11th century.

Fiscally, Constantine's reign was marked by profligacy, and he depleted the abundant imperial treasury he had inherited from Basil II (r. 976–1025) and his successors. For reasons that remain obscure Constantine debased the gold currency of the empire, the first permanent debasement of the coinage since its introduction by Constantine the Great. In Constantinople Constantine spent lavishly on both personal gifts and religious projects. Presiding over a period of economic expansion, Constantine encumbered the state by his massive expansion of the aristocracy.

In matters of provincial administration, Constantine attempted a series of reforms to varying levels of success. In the power struggle between the urban elite and the Dynatoi which was waged throughout the 11th century, Constantine made overtures towards both. He granted tax exemptions to the Dynatoi through an early form of the pronoia system and freely granted titles, privileges, and gifts of money to the civil elite. In response to the rising importance of civil judges (known as kritai) over theme commanders (strategoi) Constantine created the office of the Epi ton kriseon. Constantine attempted to reform the empire's legal system, centering on the creation of a law school headed by a nomophylax, but had limited success.

Constantine was victorious in two civil wars, foiled several coup attempts and successfully fought off a raid by the Kievan Rus', but was humiliated by the Pechenegs in the West and failed to stop the rising Seljuq Turks in the East. Though the Byzantine Empire largely retained the borders established after the conquests of Basil II — even expanding eastwards through the annexation of the Armenian kingdom of Ani — Constantine is often blamed for the poor state of the army in the years leading up to Manzikert.