History of the Raccoon Dog

This much I know from the series "It's a Dog's Life", shown on Discovery Channel, but correct me if I'm advertising nonsense:
The first canids emerged some forty million years ago on the plains of the North-American continent. They were small, relatively short legged, with a long beak and a primitive kind of carnassial teeth enabling them to rip meat of carcasses. Small rodents, reptiles, amphibians, fish, snails, grubs, maggots, worms and insects may all have been part of the diet, depending on circumstances. Thus they evolved here and there all over the continent, presumably as a number of distinct species, depending on the eco-systeem at hand.
This all went on in relative isolation, until some six-million years ago a landbridge emerged between what's now known as Alaska and Siberia. Some of the species that had been travelling or driven north, including something remakably like a raccoon dog, made the jump and found a whole continent full of big carcasses (mammoths for instance; one could feed for weeks on them with the whole family) and small rodents, reptiles, amphibians, fish, snails, grubs, maggots, worms and insects. A stroke of luck.

Everyone, except the raccoon dog, hurried on, and one million years of evolution and conquest later they had it pretty much covered, up to and including north Africa. The original colonists had evolved into some twenty species, including the European wolf.
Everyone, except the raccoon dog, because the north-east of Siberia wasn't all that bad. He travelled south as far as north Korea and even made it to Japan, where he had to wait quite some time for the first Japanese to arrive. That's as far as he would go: better to adapt to the extremes of the climate, than the wicked search for the promised land and the tiresome evolution involved. A few adaptions were quite enough. Thus he produced molars enabling a more omnivorous lifestile. He developed a wintercoat to beat all wintercoats and even took a fancy to hibernating, because, after all, it's still Siberia, and sometimes taking a nap is the best thing to do.
Thus he became suitable to everything between 30 and minus 50 degrees Celcius. Evolve? Not today thank you. Yet in time - and a lot of it - it's almost unavoidable. Five subspecies emerged:

At least some of these names suggest a geographic origin. Peninsula's and the like. I wouldn't have a clue as to the precise differences, but presumably they aren't all that big, and interbreeding will most likely occur along the borders of their respective territories.

The Russians imported the dog to start up fur farms in the Ukraine, in the beginning of the last century. When this failed due to the warm climate, they set a couple of thousands free. It was a small step for a raccoon dog, but a giant leap for raccondogkind - within half a century, that's the last centimeter on a time-scale of a kilometer, they conquered the whole of Mid-Europe. If the original ones were of different subspecies, the European population may well have evolved into Nyctereutes procyonoides europealis by now. In Germany several thousands are shot in the wild on a yearly basis, and the numbers are rising, but the population doesn't suffer too much under persecution. More end up as roadkill. In Germany there are enough of them to make it a native species, whether they like it or not. They are currently invading the Netherlands.

The white gen most probably has popped up occasionally in all subspecies, but only in the far north, in the realm of the polarbear, may it present an advantage. Of course there' weren't any polarbears as yet - they evolved even later than humans. At first there weren't any bears at all: the raccoon dog witnessed their arrival too, at a point some four million years ago.