Answer
Romanos IV Diogenes succeeded Constantine X Doukas as Byzantine emperor. Constantine's reign was marked by a series of military defeats and financial difficulties, which led to his unpopularity among the Byzantine nobility and military. In 1071, Romanos, who was then the doux of Cappadocia, led a revolt against Constantine and proclaimed himself emperor with the support of the army. Constantine was forced to abdicate and died shortly after.