This does not look that much different from knäckebröd, the (cheap) cracker bread you can still in the modern day buy in literally every supermarket of Sweden and Finland. The only difference I can see is that knäckebröd is always made with rye flour. The more artisanal / traditional varieties even come with the funny hole in the middle, that was in The Olden Times used to hang the breads on a pole in the roof above the stove.
You can buy Swedish knäckebröd in many US grocery stores. Look in the aisle with the cheese & crackers style crackers, it's labeled "Wasa crispbread" (google those words for pictures). The multigrain is good.
Trader Joe's carries Norwegian dried flat bread of some sort, but it's different. More seeds and way more dense.
However, you absolutely cannot get good rye bread anywhere in the western US. I've never spent time on East coast, maybe one of the immigrant-heavy areas might have it. Whatever is labeled as rye bread here (Jewish rye, Russian rye, ...) is different from the rye bread in the Nordics.
You can buy blood pudding in any supermarket in Sweden. It reminds you a bit of blood sausage. It's quite different from this kind of hard bread though.
Slaughter season is coming up, and the stores will start offering buckets of blood for sale. Blood sausage is still traditionally made in many homes here in Iceland.
If you're curious about ancient cuisines and want to see what the food may have looked like, check out the YouTube channel "Tasting History"[1]. The host re-creates recipes from original sources, which is often difficult given the lack of clear instructions and vastly different ingredients. He has a few Viking recipes, although not as many as the ones for Roman food.
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The Wikipedia article even has in illustration of this storage method: https://en.wikipedia.org/wiki/Crispbread#Origins
Trader Joe's carries Norwegian dried flat bread of some sort, but it's different. More seeds and way more dense.
However, you absolutely cannot get good rye bread anywhere in the western US. I've never spent time on East coast, maybe one of the immigrant-heavy areas might have it. Whatever is labeled as rye bread here (Jewish rye, Russian rye, ...) is different from the rye bread in the Nordics.
Of course, it wouldn't be a viking bread without blood
https://sv.wikipedia.org/wiki/Paltbr%C3%B6d
This will be handy the next time I want to make pancakes, but I'm out of buttermilk.
[1] https://www.youtube.com/c/tastinghistory
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We eat them weekly with dung smoked lamb and plenty of butter.