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Life of Constantine

Eusebius of Caesarea · 345

A biography written by Eusebius of Caesarea praising Constantine, the main source for stories like his vision before battle and his church building.

This biography by a contemporary bishop is the key source for Constantine's religious conversion and reign.

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Title page of a book reading 'Ecclesiastical History: The Life of the Blessed Emperor Constantine, in four books, from 306 to 337 A.D., by Eusebius Pamphilus', London, Samuel Bagster and Sons, 1845. Includes a library stamp and a publisher's ornament.
Eusebius of Caesarea, Life of Constantine, 345 AD. English edition, London, Samuel Bagster and Sons, 1845.

About this source

What it is

Life of Constantine is a work in Greek written by the bishop Eusebius of Caesarea in the 4th century, left unfinished at his death. It is divided into four books covering Constantine's rise, his wars, his religious policies, and his death.

Why it matters

Eusebius knew Constantine and had access to his letters, making this one of the richest sources for his reign, including the famous story of his vision before the Battle of the Milvian Bridge and his role at the Council of Nicaea. But Eusebius openly admired Constantine and compared him to Moses, so scholars treat the book as a glowing tribute rather than neutral history, one that likely leaves out anything unflattering.

Why it matters

Look closer

  • Why might a bishop who owed his position to Constantine write such a flattering account?
  • What does comparing Constantine to Moses suggest about how Eusebius wanted readers to see him?
  • What might be missing from a biography written to glorify its subject?

This book is part of the curated material that grounds the AI version of Constantine the Great on Humy.ai — when students ask about related events, the AI can quote it and cite it.

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Manuscript page of handwritten Greek text in brown ink on cream parchment, with a decorated red and gold initial letter at the left margin. A dark ink blot is visible in the middle of the text block. The script is a cursive Greek hand, and the page appears to be from a 16th-century codex.Document

Secondary source

Edict of Milan

Constantine the Great · 313 AD

Woodcut-style medallion portrait in profile of a man in a plumed helmet with a laurel wreath, holding a spear, with the inscription CONSTANTINVS MAX AVG around the rim. Above it a Roman-numeral heading and German text; below, German text and a monogram M 2 on a book page.Artifact

Secondary source

Woodcut Portrait of Constantine the Great

Josse van Gietleughen

Photo of the south-facing attic inscription on the Arch of Constantine in Rome: a large carved Latin inscription in two rows of capital letters on pale marble, flanked by two statues of captive or attendant figures, with a blue sky above.Artifact

Primary source

Arch of Constantine

Roman Senate · c. 312-315

Medieval illuminated manuscript page with four framed scenes in gold and blue panels. Bottom left shows a bishop with halo baptising a nude figure in a font of flames, while a crowned figure looks on. Other panels show standing saints and a scene of a figure with a torch.Painting

Secondary source

Constantine the Great Baptised by St Sylvester

c. 1200

Title page of a 1684 printed book: 'L. Caecilii Firmiani Lactantii, De mortibus persecutorum, liber; cum notis Johannis Columbi ad Gisbertum Cuperum', printed at Aboae by Johannes Winter in Finlandia. Below the text is a woodcut of a pelican-like bird with young on a branch, and a faded library stamp reading 'Bibl. Collegii ... Augsburg'.Book

Secondary source

De mortibus persecutorum

Lactantius · after 316

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