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Secondary sourceBookearly 3rd century AD

Roman History, Book 68

Cassius Dio · early 3rd century AD

A surviving account by the historian Cassius Dio describing Trajan's reign, wars, and character, written about a century after his death.

This is the main surviving historical narrative of Trajan's reign, including his wars and character.

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Dark brown cloth book cover with a white library label reading UC-NRLF and barcode $B 501 045, and a debossed decorative emblem with lettering in the center. The spine is visible on the left edge.
Cassius Dio, Roman History, Book 68 (epitome), early 3rd century AD.

About this source

What it is

This is part of Cassius Dio's Roman History, written in the early 3rd century AD, long after Trajan's reign. The surviving version is an epitome (a shortened later copy) covering Trajan's Dacian and Parthian wars and his personal character.

Why it matters

Dio's account is the main surviving narrative of Trajan's reign and includes a well-known description of both his virtues and his vices. Because Dio wrote roughly a century after Trajan's death, using earlier sources now lost, historians must weigh his account carefully rather than take it as an eyewitness record.

Look closer

  • Why is a historian writing a century later a different kind of source than a contemporary speech or inscription?
  • What might be lost or changed between Dio's original text and the surviving shortened epitome?
  • How does Dio balance Trajan's virtues and vices, and why might that balance matter?

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

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Tall marble Trajan's Column in Rome, a fluted column with spiral relief bands, topped by a bronze statue on a balcony platform. Behind it is a domed church with a lantern and tall buildings under a clear blue sky.Sculpture

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Trajan's Column

Apollodorus of Damascus · 113 AD

Plan drawing of the Imperial Fora in Rome. Labeled features include Trajan's Forum, Trajan's Column, Basilica Ulpia, Temple of Trajan, Libraries, Markets of Trajan, Forum of Augustus, Forum of Nerva, Temple of Peace, Forum of Caesar, and Curia, with a scale bar in metres and feet.Artifact

Primary source

Trajan's Forum

Apollodorus of Damascus · c. 100-113 AD

Plain red cloth book cover with fine vertical ribbed texture and a darker spine edge on the left side. No title or text is visible.Speech

Primary source

Panegyricus

Pliny the Younger · c. 100 AD

Front view of the Arch of Trajan in Benevento, a white marble Roman triumphal arch with carved relief panels and a long inscription on the attic, under a clear blue sky. Tourists stand on the paved square at left, and a tour bus and a small rounded shrub are visible on the right.Artifact

Secondary source

Arch of Trajan at Benevento

114-117 AD

Marble head sculpture of a man with short, combed, curled hair over the forehead, a stern brow, a straight nose, and a slight closed-mouth expression. The head rests on a plain base against a brick-colored wall.Sculpture

Primary source

Portrait of Trajan

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