Preserved by the acid, oxygen-free conditions in peat bogs, bog bodies have been discovered in the peat bogs of Britain and Northern Europe — and elsewhere in the world. Some date back to 8000 BC, while others are as recent as the Second World War, with the flesh so perfectly preserved that the best examples retain their skin, nails, hair — even facial features. 

Their excellent state of preservation, coupled with science and comparative history, has allowed archaeologists and scientists to piece together some of the details of the lives of these remarkable cadavers. So how is it that these bog bodies exist — and exactly what secrets from history has the peat preserved?

The Preservative Properties of Peat

Bog bodies exist because of unique environmental circumstances that preserve organic material.

Peat bogs began life as shallow lakes and ponds. They owe their special properties to sphagnum, a particular breed of moss that grows about them. Sphagnum soaks up the water that forms the ponds and releases a compound that binds nitrogen and calcium to it, creating an acidic, anaerobic environment that inhibits bacterial activity. 

This oxygen-deficient atmosphere prevents organic material from entirely decaying, meaning that dead plant material in the ponds does not fully decompose, instead building up in compressed layers. As time goes on, the ponds disappear, transformed by the combined effect of the sphagnum absorbing the water and the buildup of organic material. Instead, peat bogs remain, formed from the payers of partially decomposed vegetation.

Once formed, the unique environment of peat bogs continues to preserve other organic materials in their airless, acidic environment, slowing the rate of decomposition. At the same time, the acid of the sphagnum moss tans anything that falls into them with a reddish tinge. 

These environmental conditions preserve organic material. Wood, hide — even certain foodstuffs have been found perfectly preserved by peat. So too, has human flesh.

However, one thing peat bogs cannot preserve is bone. This is because the tannins in the acidic peat speed up bone decay, warping any bodies in peat bogs into a sack-like appearance. 

However, acidic conditions alone do not guarantee optimal organic preservation; the right temperature is the final ingredient in successful peat bog preservation. Bacteria cannot grow in temperatures below 4 degrees Celsius. This is why peat preserves best in the winter in northern European regions — and so many Northern European countries such as Ireland, mainland Britain, Denmark, Germany and the Netherlands have yielded preserved bodies from their peat bogs. 

Science and the Lives of the Bodies 

As with other mummies, analysis of bog bodies can produce evidence that helps archaeologists piece together general information on life in the European bronze and iron age — the era many of the bodies date to. This information includes:

Diet

Experts can learn about the diet of deceased individuals by taking samples from human remains and analysing the levels of specific elements present. However, in bog bodies, the contents of the stomachs are preserved along with the body, allowing archaeologists to identify the types of food eaten as the deceased’s last meal.

Many of the bog people seem to have mainly consumed vegetarian last meals — in some cases consisting of waste products such as weed seeds or chaff generally fed to animals or eaten in times of hardship. Others, such as Grauballe Man, discovered in Denmark during the 1950s, ate a last meal consisting of over 60 species of seeds, one or two cereals and only a little meat.

These meals do not seem representative of the everyday diet, with some speculating that they could be the last meals of condemned criminals. However, other last meals seem to have a ritual element. For example, Lindow man’s final meal, which consisted of a burnt cereal cake, had traces of mistletoe, suggesting a ritual element.  

While these last meals may not represent everyday diets, bog bodies can still provide plenty of evidence of how healthy life was in their societies.

Health

Some bog people show signs of good health. Old Croghan Man, discovered in June 2003 in an Irish peat bog, lived between 362 and 175 BC during the Iron Age. Although only his upper torso survives, experts have calculated his height from his arm span. From this, it appears Old Croghan man stood at an impressive 6ft 5 inches tall.

Old Croghan Man was clearly a fit and healthy individual. Besides being tall, his arms show he had substantial muscle development. In addition, analysis of his body shows that throughout most of his life, he was well nourished, with a rich meat-based diet. His manicured fingernails and unmarked hands also speak of a life of relative ease; privileged and free from manual labour.

However, not all bog people enjoyed such a healthy life, with many showing signs of disability and social disadvantage. Before she was consigned to her bog, sixteen-year-old Yde Girl seemed to have lived a life blighted by disadvantage. Her body was wrapped in a shabby cloak, indicating her poverty — or, at the very least, her lack of social worth to those who disposed of her. In addition, her body shows signs of a slight scoliosis of the spine, which caused her to rest her weight on her right foot, as indicated by the callusing on her right big toe. This would have caused Yde Girl to walk with her foot slightly twisted inwards, giving her an awkward gait.

However, even the most privileged bog people were plagued with ailments indicative of the times they lived in. Old Croghan Man has been assumed to be a member of a local elite because of his pampered appearance. However, Harris lines on his teeth indicate that a period of malnutrition during his childhood interrupted his development — a testament to the uncertainty of life for the whole social spectrum in Iron Age communities — and at some point in his life, he suffered from pleurisy. Lindow man’s hands also show few signs of manual labour — but he still suffered from roundworm and whipworm.

Trade and International Links

Bog bodies also offer evidence for the close links between distant communities previously assumed to be remote and detached from mainland Europe. 

Clonycavan Man, discovered not far from Old Croghan Man in 2003 and dated to between 392 and 201 BC, had his hair dressed with a type of Iron Age hair gel containing vegetable fat and pine resin. However, the resin was not local. Instead, it seems to originate from either the southwest of France or Spain — indicating sophisticated trade links between Ireland and the continent must have been in place during the iron age. Similarly, strontium isotope analysis of the clothing and body of Haraldskær Woman, who was found in a Jutland bog, revealed that although she had grown up in Denmark, she had travelled a considerable distance away, probably to southern Europe.

Verification of Ancient Texts

Hairstyles on bog bodies are also significant because they can corroborate information from ancient texts, confirming the accuracy of ancient accounts of northern European societies written by outsiders. For example, in the 1940s and 50s, two male bog bodies were discovered in the Schleswig-Holstein area of Germany. Respectively known as Osterby Man and Dtagen man, both wore their hair in the Suebian knot, a hairstyle described by Tacitus in his Germania as the traditional hairstyle of the free male warriors of the Suebian tribe:

Now I must treat of the Suebi …….. One mark of the race is to comb the hair back over the side of the head and tie it low in a knot behind: this distinguishes the Suebi from other Germans and the free-born of the Suebi from the slave. In other tribes, whether from some relationship to the Suebi or, as often happens, from imitation, the same thing may be found, but it is rare and confined to the period of youth. Among the Suebi, even till the hair is grey, the rough locks are twisted backwards and often knotted on the very crown: the chieftains wear theirs somewhat more ornamentally, to this extent interested in appearances, but innocently so.( Tacitus, Germania, 38.)

Death

The lack of fresh vegetables and meat found in many of the bog bodies could also indicate that most bog people died and were buried in the winter or early spring. This would also explain the exceptional state of preservation of the bodies as the low temperatures inhibit the growth of bacteria, ensuring the body tissues were pickled and soaked in bog acid and so protected by the time the temperatures began to rise and decay became a threat.

The bodies also offer clues to the nature of death. But the manner of death is a matter of debate amongst experts.