Crispus (299/305-326) was the first-born son and initial heir to Emperor Constantine I and his first wife Minervina. When his father had to eventually put aside Minervina to marry Fausta for political reasons, he did not dismiss his son but continued to care for him and would have named Crispus his heir.

Crispus was declared as Caesar in 317, a prince of the empire, and was made commander of Gaul. He led many victorious military campaigns against the Alamanni and Franks, securing the Roman presence in Gaul and Germania. He also fought alongside his brother against the hostile Emperor Licinius, building upon his already illustrious reputation with even more outstanding victories. Crispus was loved by many, almost as admired and revered as Constantine himself.

However, in a shocking turn of events Crispus was executed on the orders of his father in 326. It is unknown what truly was the cause for such action, but the execution of Fausta only a few months later has led many historians to link the two, whether it be a conspiracy against Crispus by Fausta to ensure her own sons became heirs or, less likely, that there had been an illegitimate love affair between the two that Constantine had discovered. Either way, Crispus was killed and his name never mentioned again, deleted from all official documents and monuments.