君士坦丁九世
Constantine IX Monomachos, Latinized as Monomachus (; c. 1000 – 11 January 1055), reigned as Byzantine emperor from June 1042 to January 1055. He had been chosen by Empress Zoë Porphyrogenita as a husband and co-emperor in 1042, although he had been exiled for conspiring against her previous husband, Emperor Michael IV the Paphlagonian. They ruled together until Zoë died in 1050.