FYI, in the old herbals, lettuce is usually labeled "lactuca" not "lactis" (and English herbals typically used the Latin word "lactuca" as well).
Greens were not especially popular in England in the middle ages. Some people ate them and grew them but they were not commonly grown or imported to the extent that they are today. Bread (and later the potato) was a mainstay of their diets. If you look at many pictures of table settings in old manuscripts, you'll find a fair amount of variety at the king's table (and in the accounting ledgers of kings), but images of common people and even some of the lower nobility often show nothing but bread and sausage. Toward the south, variety increased.
Greens were not especially popular in England in the middle ages. Some people ate them and grew them but they were not commonly grown or imported to the extent that they are today. Bread (and later the potato) was a mainstay of their diets. If you look at many pictures of table settings in old manuscripts, you'll find a fair amount of variety at the king's table (and in the accounting ledgers of kings), but images of common people and even some of the lower nobility often show nothing but bread and sausage. Toward the south, variety increased.