Roman writers paint a sinister picture of the religion of the Celts and their neighbours: human sacrifices, the cult of the severed head, ghastly rituals in gloomy forest clearings.
Much of this is borne out by the archaeological evidence. From the bogs of northern Europe have come chance discoveries of well preserved corpses, not recent murders as is often suspected when they first come to light, but the victims of Iron Age rituals, brutally dispatched and cast naked into pools or lakes.
These unfortunate bog sacrifices (both men and women) have given us a wealth of detail about Iron Age life - for example about health (from their well preserved intestinal parasites, for instance) and hairstyles, and even the victim's last meal - usually a mixture of plants whose composition suggests that the sacrifices were made at the winter solstice.
Less dramatic but more spectacular are the other sacrificed objects which were deposited in watery places - pools, lakes and rivers. These include many fine bronzes, especially parade armour and weapons.
A particularly rich find, including swords, horse trappings, shields, a cauldron and a slave chain, was made in the then lake of Llyn Cerrig Bach on Anglesey, stronghold of the Druids.
Classical sources show that the Druids were the religious leaders of the Celts of Britain and Gaul: they probably had their counterparts among the other communities of Europe.
Votive deposits were not confined to watery places. Deep shafts, often in square enclosures, and storage pits on settlement sites, like Danebury hillfort, often contain ritual deposits of animal carcasses - whole dogs, dismembered horses, ravens or even human bones, though these may have been from long-dead people.
Severed heads, whether from venerated ancestors or butchered enemies, adorned the gateways of many a hillfort or were displayed in shrines like that at Roquepertuse. Although Celtic worship often attached to natural places like groves and springs, small shrines were also constructed.
