A caesareum was a temple devoted to the Imperial cult. Caesarea were located throughout the Roman Empire, and often funded by the imperial government, tending to replace state spending on new temples to other gods, and becoming the main or only large temple in new Roman towns in the provinces. This was the case at Évora, Vienne and Nîmes, which were all expanded by the Romans as coloniae from Celtic oppida soon after their conquest.

Source: Roman temple – Wikipedia