- The Romans operated between 20 to 26 Alpine Infantry Cohorts and one Cavalry Cohort, across the Frontiers of the Roman Empire.
- They were recruited from the Alpine Tribes who inhabited the Alpine Mountain ranges surrounding Northern Italy.
The Roman Conquest of the Alps (25-14 BCE):
- In 25 BCE, Augustus decided that the Alpine Passes should belong to Rome, and determined to end the dominance of the old Etruscan and Ligurian Tribes who had still been resisting Rome up until this time, by harassing the nearby valleys or charging exorbitant tolls on the Passes.
- The Three Alpine Passes became Provinces known as Tres Alpes, and manned by 7 Cohorts.
Alpes Poenninae
- Consequently, in 25 BCE, the Salassi were the first to be invaded and 44,000 were sold into slavery by General Murena.
- Their territory then became the Province of Alpes Graiae et Penninae in 7 BCE.
- The capital was at Aosta.
Alpes Cottiae
- By 15 BCE, the Kingdom of the Taurini, under King Cottius, was annexed, although he remained in charge and was appointed Prefect of the New Province.
- The Capital was at Susa.
Alpes Maritimae
- By 14 BCE, the last Alpine Region reaching down to the Mediterranean sea, and occupied by the Ligurians, became a Roman Province.
- The capital was at Cemenelum, now a suburb of Nice.
Raetia (12 Cohorts)
- By 15 BCE, the Alps of Switzerland and the Tyrol, which were occupied by the Raeti, had become a Roman Province.
- The capital was at Avenches and later at Augsburg.
Vindelicia (2 Cohorts)
- In 15 BCE, the area of Germany south of the Danube, and occupied by the Vindelici, had also been conquered.
- The capital was at Augsburg.
Noricum (4 Cohorts, 1 Cavalry Cohort)
- Annexed in 16 BCE, by the Governor of Illyricum, it constituted the Eastern alps of Austria.
- Noricum supplied one Cavalry Cohort, the ‘Ala Noricum’.
- The capital was at Virunum.
Aosta, capital of Alpes Poeninae