In my research, I didn't really find anything about Viking use of burning oil on ships or anywhere actually; the closest it came was the use of fire ships, although red hot/flaming/boiling stuff was used against them in multiple cases. This does not mean it didn't happen, it just means that nothing exists on the first few pages of google to verify its use.
Apparently berserker type behavior, killing indiscriminately and being unable to stop, was present in a lot of armies even among groups that were all for showing mercy, not just vikings, although drugs could certainly facilitate this (I didn't fact check the use of these drugs, but I can if needed).
The flammable oils were an idea of my own, a very slight diversion from historical vikings which I don't see any reason to consider void or the sort. We're all going to be different from whom we're based off in some shape or form after all.
Grunter not every loving soldier is going to be in one huge army, if you were pillaging the land they would be in small groups.
For Stormemark troops not to get anything, rebels burn down houses and retreat.
Lol, I hope you aren't telling me how my countries military operates, we all have different tactics and moving around in one large horde is more affective than smaller packets, and even then these small groups would have enough troups to send rebels off into hiding. And even then, a small group of better trained, better equipped and bloodthirsty vikings will intimidate even a larger force of under-trained, under-equipped rebels who are unorganized (because
rebels) and have low morale because at the moment they have to cope with the knowledge that two countries are invading them with the intent of annexation.
However, if you're implying that for your own peoples, that'll make invading much easier on my side, that way our forces can easily wipe out the forces faster and more effectively if their broken up into smaller pockets of resistance, and thus even more unorganized.
Messengers are sent inland to declare that if the stormlands peacefully surrender to Stormemark now and with the land they hold now, exempting contested lands, their land will be converted to a Stormemark state and noble families will have a chance to become governers over said state. Otherwise, the Stormefleet and land forces will continue their assaults and unnecessary deaths will continue.