# Second Punic War Begins (-218)

URL: https://roman-history.com/timeline/-218-second-punic-war-begins
Location: Western Mediterranean and Italy
Categories: battle

Hannibal crossed the Alps after conflict over Saguntum, opening the Republic's gravest external crisis.

## Why it matters
The war tested Rome's alliance system and reshaped Mediterranean power.

Ruler at the time: [Roman Republic](https://roman-history.com/rulers/roman-republic)