Immigration was one of the factors that contributed to consolidating the economic and demographic development of Tarraco.

Many immigrants arrived in Hispania throughout the first half of the 1st century BC. They came from Italy, Greece and the East in the hope of improving their economic and social situation through commerce and agriculture.

A study of Roman Republican inscriptions found in Tarragona provides us with information about the inhabitants of the city at the time. The population was largely made up of retired army veterans, immigrants from various places, artisans, traders and public officials.

Indigenous peoples were probably still in the majority, although their degree of Romanization was probably such that Latin had become more important than the local Iberian language, although without completely eliminating it.

The names found on the inscriptions (Aemilius, Caesius, FLavius, etc.) show us that Italic families had established themselves in Tàrraco, as well as families from Aquileia (Annius) or Capua (Veicus).