Swedish sour herring is…something else.
My grandfather used to make it, it is common here on the coast, but that is NOTHING like that cruel piece of food culture from Sweden. My girlfriend is Swedish and she asked me if I knew that Swedish Surstrømning is different from the semi-evil stuff my grandfather made. I told her, yes, I very much know that. The Swedish one smells like death. But sure, it is healthy and all that. Eddible in a war sone or if I am starving. Thankfully, I have never truly starved.
Edit: Sweden actually sent a lot of it to Ukraine early in the war (I mean, it is food, healthy and can last forever). Ukrainians bombed Russian positions with it, using drones, as a joke in several videos.
addendum: I should also be serious and note that several Ukrainians also loves it. It is not so different from the evil fermented stuff they have in eastern Europe.

