The dead are associated with many beliefs. There is an inherent danger in any corpse, whether it is a relative who passed away recently, a criminal executed for their crimes or a body washing ashore. Denmark is a nation of islands and peninsulas and everywhere are beaches. Ships passes constantly through Danish waters moving from the North Sea to the Baltic Sea and back, and travelling by ship was for centuries the fastest way to get from one part of the country to the next. Sailing is not withput risk. Sailors might fall overboard, or their ship might sink. From this bodies would drift to shore. Sometime people known to the local community, but more often strangers with no one to bury them and no one to mourn them. In Danish the body is known as a strandvasker, and the undead being that haunts in their place is the strandvarsler.
The strandvarsler is a peculiar undead whose main goal is to ensure a proper burial, and though frightening it does not seem to be particularly dangerous to the living, though it is not recommended, that one steal from the corpse lying in the surf. It might grab you and force you to carry it to the local graveyard. Getting the body into the graveyard might be an issue, as the nisse guarding the place (called kirkegrim) would fight the strandvarsler trying to hinder its access.
The strandvasker and the strandvarsler are both associated with some interesting beliefs and customs in late 18th century and 19th century Denmark making it a suitable vaesen for the roleplaying game Vaesen – Nordic Horror Roleplaying, and you can download for free the Strandvasker & Strandvarsler from DrivethruRPG. The article includes an extended article summarizing customs and beliefs regarding bodies washing ashore, the how they are buried and how they manifest as supernatural beings.
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