Minervina

[…] Minervina was the first wife of Constantine the Great.

Constantine either took her as a concubine or married her in 303 AD, and the couple had one son, Crispus. Nothing else is known about Minervina. Crispus' father served as a hostage in the court of Eastern Roman Emperor Diocletian in Nicomedia, thus securing the loyalty of Caesar of the Western Roman Empire Constantius Chlorus, father of Constantine and grandfather of Crispus.

When Constantine wanted to strengthen his bonds with the other Tetrarchs, in 307 AD he set aside Minervina and married Fausta, daughter of Augustus Maximian.

The marriage of Constantine to Fausta has caused modern historians to question the status of his relation to Minervina and Crispus. If Minervina was his legitimate wife, Constantine would have needed to secure a divorce before marrying Fausta. This would have required an official written order signed by Constantine himself, but no such order is mentioned by contemporary sources. This silence in the sources has led many historians to conclude that the relationship between Constantine and Minervina was informal and to assume her to have been an unofficial lover. However, Minervina may have already been dead by 307. A widowed Constantine would need no divorce.

Neither the true nature of the relationship between Constantine and Minervina nor the reason Crispus came under the protection of his father will ever probably be known. The offspring of an illegitimate affair could have caused dynastical problems and would likely be dismissed, but Crispus was raised by his father in Gaul. This can be seen as evidence of a loving and public relationship between Constantine and Minervina which gave him a reason to protect her son.

The story of Minervina is quite similar to that of Constantine's mother Helena. Constantine's father later had to divorce her for political reasons, specifically, to marry Flavia Maximiana Theodora, the daughter of Maximian, in order to secure his alliance with his new father-in-law. Constantine in turn may have had to put aside Minervina in order to secure an alliance with the same man. Constantius did not however dismiss Constantine as his son, and perhaps Constantine chose to follow the example of his father.

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Wikipedia