Antoninus Pius also known as Antoninus, was Roman Emperor

Roman Emperor

The Roman emperor was the ruler of the Roman State during the imperial period . The Romans had no single term for the office although at any given time, a given title was associated with the emperor...

 from 138 to 161. He was a member of the Nerva-Antonine dynasty and the Aurelii. He did not possess the sobriquet

Sobriquet

A sobriquet is a nickname, sometimes assumed, but often given by another. It is usually a familiar name, distinct from a pseudonym assumed as a disguise, but a nickname which is familiar enough such that it can be used in place of a real name without the need of explanation...

 "Pius

Pius

-Popes:* Pope Pius I, saint, Pope 140/142 to 155* Pope Pius II, Pope 1458 to 1474* Pope Pius III, Pope in 1503* Pope Pius IV, Pope 1559 to 1565* Pope Pius V, saint, Pope 1566 to 1572* Pope Pius VI, Pope 1775 to 1799* Pope Pius VII, Pope 1800 to 1823...

" until after his accession to the throne. Almost certainly, he earned the name "Pius" because he compelled the Senate

Roman Senate

The Senate of the Roman Republic was a political institution in the ancient Roman Republic, however, it was not an elected body, but one whose members were appointed by the consuls, and later by the censors. After a magistrate served his term in office, it usually was followed with automatic...

 to deify

Imperial cult (ancient Rome)

The Imperial cult of ancient Rome identified emperors and some members of their families with the divinely sanctioned authority of the Roman State...

 his adoptive father Hadrian

Hadrian

Hadrian , was Roman Emperor from 117 to 138. He is best known for building Hadrian's Wall, which marked the northern limit of Roman Britain. In Rome, he re-built the Pantheon and constructed the Temple of Venus and Roma. In addition to being emperor, Hadrian was a humanist and was philhellene in...

; the Historia Augusta, however, suggests that he may have earned the name by saving senators sentenced to death by Hadrian in his later years.
He was the son and only child of Titus Aurelius Fulvus

Titus Aurelius Fulvus

In the 1st century there were two men with the name Titus Aurelius Fulvus. One was the paternal grandfather and the other the father to the Roman Emperor Antoninus Pius....

, consul

Consul

Consul was the highest elected office of the Roman Republic and an appointive office under the Empire. The title was also used in other city states and also revived in modern states, notably in the First French Republic...

 in 89 whose family came from Nemausus

Nemausus

Deus Nemausus is often said to have been the Celtic patron god of Nemausus . The god does not seem to have been worshipped outside of this locality...

 (modern Nîmes

Nîmes

Nîmes is the capital of the Gard department in the Languedoc-Roussillon region in southern France. Nîmes has a rich history, dating back to the Roman Empire, and is a popular tourist destination.-History:...

).