North Germanic peoples
Vikings were also active in Francia. Some of these Vikings would sail through the Strait of Gibraltar and pillage the coasts of the Mediterranean Sea. In the early 10th century, a group of Vikings under the leadership of Rollo settled in Rouen, France, and established the Duchy of Normandy. The descendants of these Vikings, known as the "Normans", would in the 11th century conquer England, Southern Italy, and North Africa, and play a leading role in launching the Crusades. Sub-groups of the Normans include Anglo-Normans, Scoto-Normans, Cambro-Normans, Hiberno-Normans and Italo-Normans.
Ímar
Norse contact with Scotland predates the first written records in the 8th century, although the nature and frequency of these contacts is unknown. Excavations on the island of Unst in Shetland indicate that Scandinavian settlers had reached there perhaps as early as the mid-7th century and from 793 onwards repeated raids by Vikings on the British Isles are recorded. "All the islands of Britain" were devastated in 794 with Iona being sacked in 802 and 806. The Frankish "" may record the conquest of the Inner Hebrides by Vikings in 847. Scholarly interpretations of the period "have led to widely divergent reconstructions of Viking Age Scotland", especially in the early period, and Barrett has identified several competing theories, none of which he regards as proven. Ó Corráin notes: "when and how the Vikings conquered and occupied the Isles is unknown, perhaps unknowable".