Carthage was a rival for Mediterranean Sea power for the Roman Republic, who wanted to take over the whole western Mediterranean Sea. Carthage was a large obstacle to that. So, in 264 BC, the Romans responded to a plea for help by some rebels in Messina, and landed an army in Sicily. This started the First Punic War. The Romans then invaded the Carthaginian holdings in Sicily, and the Carthaginian generals could not stop them. Even at sea, the Romans were able to copy the Carthaginian bireme ships and win several major victories on the sea, though the Carthaginians had long fought at sea and the Romans were new to this. 