After the fall of the Western Roman Empire in the late 5th century, several tribes and groups swarmed into Europe, significantly impacting the cultural and political landscape. Among the options provided, the most relevant answer is:
Lombards and Goths
The Goths, including the Visigoths and Ostrogoths, were among the first tribes to move into Roman territories, while the Lombards entered Italy later. The Celts and Picts were present in Europe prior to the fall of Rome, and the Vikings and Normans emerged in later centuries, impacting Europe during the medieval period.