During the Migration Period, the Slavic tribe of the Carantanians migrated into the Alps in the wake of the expansion of their Avar overlords during the 7th century, mixed with the Celto-Romanic population, and established the realm of Carantania, which covered much of eastern and central Austrian territory. In the meantime, the Germanic tribe of the Bavarians had developed in the 5th and 6th century in the west of the country and in Bavaria, while what is today Vorarlberg had been settled by the Alemans. Those groups mixed with the Rhaeto-Romanic population and pushed it up into the mountains.