Bodies of the Bogs

I read a very fascinating book about bog bodies and felt the need to make an illustration about it :-)

During the Iron age until well into the Roman times, there seems to have been a morbid ritual in Northern Europe: people would be violently murdered and thrown in to bogs, where their bodies would be so well preserved we still find their mummified remains today. Why did they do this? Who were these people? It is still a mystery!