Nordo-Celtic knot symbolizing the Drakkar longships paired with the central Icelandic Vegvisir ("sign post"), which is a type of late medieval bind-rune that was a magic sigil to prevent the bearer from getting "lost in the storm". The Vegvisir is often erroneously identified as a Viking-age rune.
The signs and staves seen here can be found in Icelandic grimoires, some from the 17th century, some from later times though all of them seem to be related. The origin of this peculiar Icelandic magic is difficult to ascertain. Some signs seem to be derived from medieval mysticism and renaissance occultism, while others may be related to runic culture and Germanic belief in Thor and Odinn. Most magic mentioned in court records can be found in grimoires kept in various manuscript collections.