During his consulship, he campaigned in Gallia Transalpina (in the modern day Auvergne and Rhône-Alpes regions) with Gnaeus Domitius Ahenobarbus against the Gallic tribes of the Allobroges and Arverni.
[4] After his consulship expired, he replaced Domitius Ahenobarbus as proconsul in Gaul (120 BC), during which time he completed the defeat of the Allobroges and Arverni.
[5] The triumph he held was famous for its spectacle, including the captive Arvernian king Bituitus in his silver battle armor.
From the plunder of the Auvergne, Fabius erected the Fornix Fabianus (121 BC) crossing the Via Sacra at the Forum Romanum, placing a statue of himself on top of the arch.
Upon the death of his blood uncle Scipio Aemilianus in 129 BC, Fabius presented a banquet to the citizenry of Rome and pronounced the funeral oration of the deceased general.