Hadrian had adopted to follow Trajan as emperor, but his selection was not immediately approved. Within a short time, four senators were accused of plotting treason.
Unlike Trajan’s reign of warfare and territorial expansion, Hadrian’s reign was one of peace and consolidation, except for a serious revolt in Judaea in 132 AD.
Hadrian was a cultured scholar who travelled all over the empire. He was attended to the needs of the army and the provinces. His greatest legacy to the empire was his establishment of clearly marked frontiers, putting an end to expansion.
He built walls in Africa to protect routes and in Germany he built a palisade with watchtowers and small forts to mark the edge Roman-controlled territory. In Britain, he built a stone wall.
Hadrian divided what was Roman from what was not. Apart from minor adjustments, no succeeding emperor reversed his policies.
Source: Hadrian
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