They explored Newfoundland under Leif Ericson using their characteristic longships.
After one event, these people were blasted by Alcuin in a letter addressed to Bishop Hygbald. These people hid Edmund the Martyr's head in a hedge under the command of Ivar the Boneless. They comprised the personal bodyguard of Basil II as the Varangian Guard, and regularly collected preventative tributes called the Danegeld. These people formed the Great Heathen Army after razing Lindisfarne. They explored Newfoundland under Leif Ericson using their characteristic longships. For 10 points, name these Scandinavian people who carried out devastating namesake "raids" and are erroneously depicted wearing horned helmets.
After one event, these people were blasted by Alcuin in a letter addressed to Bishop Hygbald.
Vikings [prompt on "Norse" or "Norsemen" or "Scandinavians" before mention]