Original: Julius Caesar has conquered nearly all of Gaul for the Roman Empire, however the little Armorican village has held out because the villagers can gain temporary superhuman strength by drinking a magic potion brewed by the local village druid, Getafix.
Simplified: Unlike, the rest of Gaul, this village has not been taken over by the Romans, because the people in the village drink a magic potion brewed by their druid.