Recent research, however, has challenged the idea that meat was a significant portion of the daily diet. Early Christian thought questioned meat-eating. John Chrysostom, Origen, Jerome, and others were vegetarians. Many hermits renounced meat as part of their asceticism, and of course the Church during Lent forbids eating meat in order to make a personal sacrifice while contemplating the upcoming commemoration of the Crucifixion. The Rule of St. Benedict allowed fish and fowl, but meat from quadrupeds only to aid in illness.
Outside of strict Christian communities such as monasteries, how common was meat-eating? Here's an example: during the reign of Ine of Wessex (688 - 726), there are 11 surviving lists of what was served at feasts. They mention beef, mutton, salmon, poultry, some bread and cheese, along with honey and ale. The absence of vegetables on the lists does not necessarily mean vegetables were not present. As likely an explanation is that vegetables were so commonplace and expected that they were not worth mentioning.
There are few cookbooks from the Middle Ages, but there is a way to determine diet other than written lists of recipes: archaeology, and not just from finding the remains of trash heaps in excavated villages. There are answers in the bones.
If early medieval rulers consumed copious amounts of meat on a regular basis, that would likely be reflected in their remains. But an isotopic analysis of 2,023 skeletons from a variety of socioeconomic backgrounds “found no evidence of people eating anything like this much animal protein,” says co-author Sam Leggett, a bioarchaeologist at the University of Edinburgh, in the statement. “If they were, we would find isotopic evidence of excess protein and signs of diseases like gout from the bones. But we’re just not finding that.” [link]
We are realizing that during centuries when 90-99% of the population was agrarian, the people were not just raising livestock. There must of course have been vegetables grown and used extensively, composing the largest part of the daily diet—the evidence of bones confirms it.
Let's explore a typical medieval vegetable garden next time and see what they were growing for food.