It was essentially the time of the Punic wars. And Tarragona like so many towns that were around at the time had been set up by the Phoenicians, the Greeks seemed to control further south and that was the Carthagians entered from the south and usually fought with the Romans for control of the Peninsular.

Built on patios on a 160 meter high rock, supplied from a natural harbor, The Romans, who occupied the Iberian town in the second Punic War ( 218-202 ), fortified it much more. Their chiefs Publius and Gnaeus Cornelius Scipio erected a 10 meter high wall, which is saved over a distance of more than a kilometre and can still be seen in the city today. The wall was made on a foundation of large ( "cyclopic" ) natural stones and is made up of two parallel walls, 4 meters apart. …show more content…
Three towers survive, which used to be famous Pliny the Elder, touches on them in his Natural History. Tarraco was Rome's base for further operations in Hispania, also in the wars against the Iberians, Celtiberians, and Lusitanians.

It turned into a regional capital, first off it became the Hispania Citerior, later of Hispania Tarraconensis, suggesting that there had been a praetorian or governor's palace. In 45 BCE, Julius Caesar gave the city the rights of a colonia and from this time onwards its full official name was Colonia Julia Urbs Triumphalis