Viking Age: Everyday life during the extraordinary era of the Norsemen, by Kirsten Wolf, does a good job of explaining the limits in our knowledge of the Viking Age. Author points out we “know next to nothing” about the training and education used by Scandinavians. Author guesses that homeschooling was used extensively but there is no trace of that visible in any way.
The limit in knowledge carries over to health and medicine. Author points out it is “difficult to make an assessment of the health conditions” and “little is known about the types of illnesses that were prevalent.” Author guesses that diseases such as scurvy were likely widespread. The word “probably” is used to estimate that poor sanitation and general poor nutrition were sources of many illnesses.
The isolation of settlements (remember that earlier comment that only on the coasts of Denmark and Sweden were there locations with three or four farms close together) minimized the spread of plagues and other infectious diseases, which were common on the European continent. On the other hand, families typically all slept in the same room and frequent would have farm animals sleep in the houses. That would serve as an increased risk of spreading communicable diseases when someone had caught one. Having animals sleep in the house would introduce more vectors for disease transmission.
In terms of material life, the author explains that farmhouses are well understood because many of them have been found and excavated.
In contrast, researchers are left to guess about the interior of houses, furnishings, and personal appearance since there is little evidence that survived – cloth and wood don’t last well over centuries. In four pages the following qualifiers appear on what we know of the material stuff in the life if Vikings. All comments are quotes.
“Wax candles appear to have been a rare and expensive commodity…
Presumably…
Several reports…
Walls appear to be…
Stools and chairs seem to have…
Unlikely…
Suggest…
It has been suggested…
Suggests…
Typically…
Suggest…
Probably low…
It is, however, possible…
Archaeological evidence for [types, styles, composition of] clothing… is quite limited…
Offer hints…
Scanty knowledge…”
Later on the book says that today we “know next to nothing” about the legal system was in use during the Viking Age. The written laws that survive were codified in the 12th and 13th centuries, well after the Viking era ended. That tells me that in order to sort out what law was in use during the Viking Age, researchers must filter out what they think had been added in the intervening 200 or 300 years.