In the second book of the Eyrbyggia Saga, a curious tale of a vampire is recorded. The story also appears in the books of Saxo Grammaticus, Det Kongelige Bibliotek, and was also translated by Sir Walter Scott.
Long ago, Prince Asmund of Iceland lost his way in a storm while hunting. He would have died, were it not for the kind intervention of Prince Aswid, who took him back to the hall of King Bjorn. To show his gratitude, they became blood brothers and quested to destroy all of those who worked evil.
One of them suggested, as they grew older, that they should make a death pact-- that when one of them died, the other would go to the grave with his friend. They both agreed to this and swore on their blood.
It came to pass that Aswid grew ill and died. All of the people mourned, and there was many days of funeral rites and feasting, to commemerate the fallen hero. True to his oath, Asmund followed his friend to the grave, despite the protests of other close friends and advisors. Asmund was sealed alive in the tomb with the body of his friend and many other tributes to entertain the dead in the afterlife, such as food, horses, Aswid's favorite dog and weapons.
Before Asmund had decided how best to kill himself, Aswid awoke from his death sleep. Rising as a vampire, he first consumed the body of his dog, then of the horses. He then turned his attention on his friend, and attacked him with a demonic fury. Taking up a sword, Aswid fought off his former friend.
Some three hundred years later, several daring young men set off to the tomb of the famous warriors. Despite warnings of the tomb being haunted, and of the religious implications of disturbing the dead, the brave young men went to the grave and opened it. Hearing sounds of struggle, one man volunteered to go down into the tomb. Lowering him on a rope, he went down to investigate. The friends called to him after several minutes, then were met by a great tug on the rope. They pulled the rope up, only to find an old-fashioned armored warrior at the end of it.
Trying to catch his breath, Asmund told them of the story of Aswid rising as a vampire and trying to kill him. He had been fighting for his life for three hundred years, and had succeded only when the young man had appeared, offering a distraction. With that, he fell over dead. The young men, realizing the bravery of the warrior Asmund, buried him in the tomb with full honor, their companion beside him. They took the decapitated body of Aswid out and burned it, scattering his ashes to the wind.