Why was Gaul important to the Romans?

Question

Please answer as detailed as you can! Why were they important and what did the Romans do there?

Answer 1

Gauls under Brennus sacked Rome circa 390 BC. Defense against such attacks became a primary Roman concern

In the second century BC, Mediterranean Gaul had en extensive urban fabric and was prosperous, while the heavily forested Northern Gaul had almost no cities outside of fortified compounds used in times of war. The prosperity of Mediterranean Gaul lead to Rome responding to the pleas of the inhabitants of Marseille who were under attack by a coalition of Ligures and Gauls: the Romans intervened in Gaul in 125 BC and by 121 BC they had conquered the Mediterranean region called Provincia.

Answer 2

What Was Gaul