Constantine (son of Basil I)_

Constantine was a junior Byzantine emperor, alongside Basil I as the senior emperor, from January 868 to 3 September 879. His parentage is a matter of debate, but historians generally assume him to be the son of Emperor Basil I and his first wife Maria or second wife Eudokia Ingerina; other theories include him being the son of Emperor Michael III and Eudokia. Constantine was made co-emperor by Basil in c. January 868. He was engaged to Ermengard of Italy, the daughter of Holy Roman Emperor Louis II, in 870/871, but it is not known if he married her; some sources suggest he did, and others argue that there is no concrete evidence.