Why did the Romans go to war with Carthage?
The three wars between Rome and Carthage are known as the Punic Wars (264-146 BC.) Carthage was the strongest power in the Mediterranean Sea at the time. The expanding Romans really wanted that role. Rome looked to the island of Sicily off its western coast to relieve its population pressures. Carthage controlled part of the island and wanted more of the land. Sicily was very fertile which was important for agriculture and food supply for an expanding empire. It was also an ideal location for fishing industries to develop. Having said all of this, the Punic Wars were fought primarily for economic purposes.
Rome won the first Punic War and signed a treaty with Carthage. The treaty called for Carthage to pay a hefty fine over the course of fifty years and agree not to show aggression to any of Rome's allies.
Carthage, with all of its wealth, could easily pay the fine, but it could not stomach the constant raids of its lands by Rome's allies. Having lost patience with the looting by the Numidians, Carthage acted out against them. This angered Rome, which convinced the empire to declare war again. At the end of the Punic Wars, Carthage was completely in ruin and essentially extinct. This allowed for unfettered expansion throughout the Mediterranean for the Romans.