Trying too hard to avoid cliche?

[Beoner]

Hmm, I can see ways of your ideia working, and based on all the information here you could build something very plausible with no magic involved.

I could see a civilization growing on a polar area, yet it would need some specific help of the enviroment. I would first include the rdanhenry's ideia, because indeed a underwater volcano area - we could even include geisers - would be like an oasis in the desert (and a polar region is basically a desert, except it is REALLY cold, instead of hot). This would make the area better for living. With this, you would have to think, there are not many plants that survive on a polar region, I mean, only some pines survive on north of Russia, for example, but your world is not earth, and your world doesn't have the same plants and animals Earth has - and TheHoarseWhisperer gave a good idea - so maybe it could have a plant capable of surviving on extremely cold regions, or even more than one, what would give the people there seeds/cereal/grains, or fruits, or at least wood. Of course the people would have to make a canals to the hot water get irrigate the plantations, and probably would need lots of care with the plants and stuff. The people could even have built a system to have plantations over the hot water - there are some ways, but you would need plants like rice which can grow with lots of water instead of dying like what happens with most plants.

Surviving in so cold regions would demand meat, of course, so they may have buffalos or Llamas, or another animal of your world that provides meat, wool, and maybe milk. Fish could be easly fished from the water next to the city. Fire can be come easily if you have pines, its sap (blood, I'm not sure what is right, used google translate) is extremely flamemable. With some mining - maybe an iron mine somewhere next, or faraway, from the city - they could have iron to make objects for both defense and plantation.

Remember, your world is not Earth, unless you want, so maybe it has no Tigers, but it has Ululos, which is a three headed cat 7 feet tall that eats oranges. Like what TheHoarseWhisperer said, you are looking for plausibility, not realism.

[artearth]

I love the idea of a far north civilization who uses the sea - as in, whole guilds of seafarers, from the seaweed harvesters (whole complex ecologies of sea plants and small shellfish, creating all the nutrition they woud need) to the whalers (or whatever large, blubbery creature could provide a host of other uses when triumphantly killed) to the hunters of slippery seal creatures that provide the skins for clothing, drums, waterskins, etc, to specialists mining the ocean floor for minerals and other goodies that serve the civilization. On land there are "ranchers" who grow millions of mouse sized furry creatures in bins, use their body heat for warming greenhouses, and then eat them in mass quantities. They disdain the poor teeth and flabby musculature of those grain eaters to the south, and regularly send maori style raiding parties to scatter the weak tribes living nearby. Generally speaking in biology, there is a tendency for animals in the northern range of the species to be larger than those in the south, so maybe these folks are huge, and flabby from mass consumption of fat. Smooth white skin, tattooed with squid ink, carrying obsidian spears and with bright blue eyes. I like the idea that underwater volcanos cough up minerals, and probably their theology is based on the gods that live deep under the sea. Volcanic rock signifies power, and heat=status, so the richest and most powerful folks flamboyantly waste heat, and are skinnier, since fat=survival here. They have priests of the light (summer solstice) and of the dark (winter solstice) and the whole culture revolves around the sun, essentially becoming more vicious and warlike as the sun fades, to essentially vampiric in the long months of whole dark, but then undergoing extensive rituals of fast and redemption throughout the spring to enjoy a few months of great wisdom and compassion in the summer. This is when their books are written and children are born, and then trusted monks hide the trappings of the "light" civilization away when the descent begins in the fall.