Today I was watching an old BBC documentary made in 1954 about a 2070-year-old Dane found in a peat bog in North Jutland. Archeologists had dated the body to the Early Iron Age, and I pricked up my ears when I heard that the stomach contents of his last meal were well preserved. Interesting! Apparently there was no meat in it at all. All they found were grains and seeds [surprise, surprise!] - specifically barley [the most], flaxseed and various smaller amounts of the seeds of wild plants - greens of some sort which were set out for us to see.
These iron age people did have domestic animals but they were too precious to eat except on rare occasions and there weren't enough wild animals for the population to live on.
A 'prehistoric early iron-age expert' cooked the food up into some sort of gruel and a very eminent archeologist of the time- Sir Mortimer Wheeler, interviewer and the cook ate it with some mead. They all thought it was disgusting, but the mead was ok, apparently.
Unfortunately, I believe only those in the Uk can watch the programme, but I thought I'd put the link in:
http://www.bbc.co.uk/iplayer/episode/p01819j0/buried-treasure-the-peat-bog-murder-mystery#Eiry