Pseudo-Scandinavia can be a great place to set a sandbox game. Vast oceans containing hidden islands and far off undiscovered continents, lofty mountains holding dwarven keeps and dragon hoards, swamps crawling with trolls and deep pine forests full of abandoned elven palaces.
To make the area suitable for adventure there should be a handful of small kingdoms about. Each run by their own glory obsessed warrior king and his cadre of viking stereotypes. These places should not be all powerful bureaucracies or empires. If a kingdom has more than a few hundred warriors it can muster it is probably too large. Ideally the kingdoms should be small enough that a few potent warriors would be a noticeable factor in any war between two kingdoms.
There should also be enough fertile lands about that one could forge their own town, city, castle or even kingdom. Of course these lands should be plagued by monsters, thus forging your own country could be a great drive for adventure. This may require funds to build a castle and lure citizens...I hear English monasteries have a lot of gold. This allows for viking warriors, skalds and scouts (thieves).
Of course, these lands also have many warrior pagan faiths..and the new missionaries from the south aim to change all that. This type of strife allows for many clerics to have their own goals.
And of course in this barbarous land there are old and ancient magics..but no libraries of note. A handful of private collections, much of the magic must be learned from truly ancient cave paintings, chants of isolated tribes and ancient dragon secrets. A sorcerer or witch in these lands cannot rest in quite study...they need to be constantly on the move..seeking to uncover the secrets of others before others uncover their secrets.
This type of setting allows for easily understandable player driven goals, that players can figure out without needing to read through 40 pages of setting notes. Are you a southern missionary? Convert heathens. A viking? Get to Valhalla through mashing bigger and badder monsters. A noble? clear out that dragon and use its hoard to build a castle. Wizard? find the old man of the mountains and the swamp hag..steal their secrets.
Of course, this is just human culture. I'll detail a suitable dwarven culture for Pseudo-Scandinavia next.
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