117 CEReputable sourceWell documented
The Empire at Its Greatest Extent under Trajan
On the timeline · around 117 CE ·
What happened
Under the emperor Trajan, whose conquests included Dacia and, briefly, Mesopotamia, the Roman Empire reached its greatest territorial extent by 117 CE, stretching from Britain to the Persian Gulf.
Why it matters
Trajan's reign marked the high-water mark of Roman expansion; his successor Hadrian would consolidate the frontiers rather than extend them.
Sources
- World History Encyclopedia. Trajan · Reputable source