Antoninus (86-161) was born in 86 to Consul Titus Aurelius Fulvus, and would grow up to become friend and ally to Emperor Hadrian, who adopted him as son and heir in 138. In turn, Hadrian made Antoninus adopt future emperors Marcus Aurelius and Lucius Verus as his successors
Antoninus ascended to emperor the same year of his adoption, acquiring the name Pius after he persuaded the Senate to grant Hadrian divine honours. He made few initial changes to Hadrian's arrangements and policies, and he oversaw a non-military and mostly peaceful reign, the most peaceful in the Principate's history. He was also perhaps the instigator of the first direct contact between Rome and China, confusion remaining whether Antoninus or Marcus Aurelius sent the first envoy. Antoninus Pius died of illness in 161, aged 74, and was succeeded by his adopted sons Marcus Aurelius and Lucius Verus, who reigned as co-emperors. Antoninus Pius is named as one of the 'Five Good Emperors', and was the longest reigning emperor since Augustus, surpassing Tiberius by a few months.