The cartaginians
Hamilcar Barca was one of the famous generals. He led the Carthaginian army in the first Punic War till 241 BC. His son was also a famous general, as he led the Cartaginians aganst Rome in the second Punic War. He led his army through Spain and crossed the Alps (with his 70 elephants), he won a lot of victories over the Romans but failed to capture Rome itself. In the end , he was defeated at Zama (Africa, 202 BC).
In the First Punic War, which was fought in Sicily, the rugged terrain created a stalemate in the land war. This conflict was fought mainly at sea. The Carthaginian had a very good navy and excellent sailors. Rome built a fleet from scratch, but her sailors were inexperienced. To make up for this they built a boarding bridge (the corvus) of their ships. This worked well and the Romans won several battles. However, it made the ships top heavy and vulnerable in storms. The corvus was eventually ditched. Despite this, Rome still won the final naval battle of the war. In the Second Punic War, Hannibal invaded Italy and routed the armies of the Romans and their Italian allies four times. The Romans switched to a strategy of attrition. They avoided open battles against Hannibal and harassed him. They got Hannibal stuck in the south of Italy. They concentrated on retaking Capua (Italy's second largest city) which sided with Hannibal. They then sent several legions to different parts of the south to retake towns seized by the Carthaginians. The manpower available to Rome was far greater than that of Hannibal, who was leading what was an expeditionary force. The Romans also intercepted Hasdrubal, Hannibal's brother who was taking reinforcements for Hannibal from Spain (Hannibal's power base). Rome also won a war in southern Spain , defeating the Carthaginians there, and took over this area. At this point, with no chance of getting reinforcements, Hannibal's campaign came to a dead end. Finally, the Romans started a campaign in Tunisia (Carthage's homeland) forcing Hannibal to leave Italy to fight there. They won this final battle. It was relatively easy for Rome to win the Third Punic War. The power of Carthage had been severely curtailed by the previous war.
In 237 BCE Rome took the excuse of a revolt by mercenaries to seize control of Corsica and Sardinia in breach of the treaty which ended the First Punic War with Carthage. Carthage began to conquer Spain over the next seven years, but signed a treaty with Rome in 226 BCE not to go north of the Ebro River. In 220 BCE the Cartaginians captured Saguntum, which was within the Ebro limit, but Rome used this as an excuse to declare war to confront an increasingly confident and expansionary Carthage.