Hadrian (Hadrianus) was born on January 24, 76 and died on July 10, 138, and he was Roman emperor from 117–138.

Hadrian was a distant relative of his predecessor Trajan. Trajan named Hadrian emperor immediately before his death.

Although Hadrian was a good commander, he was not able to keep all of the lands that Trajan had won. He let the farthest areas of the Middle East go.
He tried to strengthen the places where he thought the empire could defend itself. The most famous of these is Hadrian's Wall, which was built starting in 120.

In Rome, the Pantheon built by Agrippa was enriched under Hadrian and took the form in which it remains to this day.

Hadrian also changed the look of the emperors. Up to his time, all emperors had been shown looking like ideal Greek athletes, but Hadrian was bearded and other emperors would follow this new style.

Over half of Hadrian's reign was spent travelling outside Italy. Other emperors often left Rome to simply go to war, but Hadrian saw it as important to visit all parts of the empire to help keep the peace. For example, in Britain there was a major revolt in 119. Hadrian arrived and immediately started the building of the wall to keep out the Caledonians to the north. Hadrian stayed in Britannia until 122.

After his death, Hadrian was buried in a huge mound (a mausoleum) on the banks of the Tiber opposite Rome. It was later made into a castle but can still be seen today.