Constantine IX Monomachos, Latinized as Constantine IX Monomachus (c. 1000 – January 11, 1055), reigns as Byzantine emperor from June 11, 1042 to January 11, 1055.
He had been chosen by the Empress Zoe as a husband and co-emperor in 1042, although he had been exiled for conspiring against her previous husband, Emperor Michael IV the Paphlagonian.