Hadrian (/ˈheɪdriən/; Latin: Publius Aelius Hadrianus Augustus; 24 January 76 – 10 July 138) was Roman emperor from 117 to 138. Hadrian is known for building Hadrian's Wall, which marked the northern limit of Britannia. He also rebuilt the Pantheon and constructed the Temple of Venus and Roma. Philhellene in most of his tastes, he is considered by some to have been a humanist, and he is regarded as the third of the Five Good Emperors.

Hadrian was born Publius Aelius Hadrianus into a Hispano-Roman family. Although Italica near Santiponce (in modern-day Spain) is often considered his birthplace, his actual place of birth remains uncertain. However, it is generally accepted that he came from a family with centuries-old roots in Hispania. His predecessor, Trajan, was a maternal cousin of Hadrian's father. Trajan did not officially designate an heir, but according to his wife Pompeia Plotina, Trajan named Hadrian emperor immediately before his death. Trajan's wife and his friend Licinius Sura were well-disposed towards Hadrian, and he may well have owed his succession to them.