What was the cause for the first punic war? explain in detail and tell me your sources.

The First Punic War broke out because the Mamertines (in the city of Messana, now modern Messina) of Sicily both called for Carthaginian and Roman assistance for their war against Syracuse. Carthage saw this as an opportunity to consolidate its hold on Sicily, while the Romans saw Carthage as encroaching on its sphere of influence. Both Carthage and Rome saw each other as interefering in one another's foreign affairs, and the dispute escalated into open warfare.

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