Viking raid warfare and tactics
Vikings were members of tribes, originally from Scandinavia, of Norse ancestry, who gained a reputation for their raids and piracy in many parts of Europe, especially England, Ireland, and Frankish territories. The term "Viking Age" refers to the period roughly from 793 AD to the late 11th century in Europe. In this era Viking activity started with raids on Christian lands in England and eventually expanded to mainland Europe, including parts of present-day Russia. While maritime battles were rare, Viking bands proved very successful in raiding coastal towns and monasteries due to their efficient warships, and intimidating war tactics, skillful hand-to-hand combat, and fearlessness. What started as Viking raids on small towns transformed into the establishment of important agricultural spaces and commercial trading-hubs across Europe through rudimentary colonization. Vikings' tactics in warfare gave them an enormous advantage in successfully raiding (and later colonizing), despite their small population in comparison to that of their enemies.
Viking expansion
Quite extensive evidence for minor Viking raids in Iberia continues for the early eleventh century in later narratives (including some Icelandic sagas) and in northern Iberian charters. As the Viking Age drew to a close, Scandinavians and Normans continued to have opportunities to visit and raid Iberia while on their way to the Holy Land for pilgrimage or crusade, or in connection with Norman conquests in the Mediterranean. Key examples in the saga literature are Sigurðr Jórsalafari (king of Norway 1103-1130) and Røgnvaldr kali Kolsson (d. 1158).