In my previous post, I mentioned the bog people in the Irish National Museum. I meant to include a link that describes the bog bodies and the latest theory about them.
The bog bodies are remains of executed victims from more than 2,000 years ago, who were thrown into bogs, preserving the corpses. The most recent theory, based on jewelry and ornate grave goods found at excavation, is that they are the bodies of kings or king contenders who were sacrificed to the gods when a new king was inaugurated. Another fact supporting the theory of royal sacrifice is that one of the bodies still has its fingernails intact, and the nails indicate that the person did not perform manual labor. The exhibit was fascinating, if a bit gruesome.
You can find more on the bog bodies here. (Warning: the photos are graphic.)