and if there were colder winters in Europe on a regular basis, there would not have been as many battles/wars.

As per the example, winter was no obstacle to fighting, so that does not really follow.

stevesim:

in North America, for example, there were some battles fought during cold weather, but even the tribal conflicts in pre-Columbian Northern America were put on hold during the winter months.

Sure, seasonal fighting exists, but winter is not all bad for fighting. Depending on terrain and technology a frozen winter can give better conditions for raids and war then a swampy summer. And seasonal pauses are unstable, because if some tribe figures out how to attack off-season they often win, and then everybody starts doing it.

Anyway, if you are going with northern Europe as part of the countries you mentioned here:

stevesim:

it's not an accident that the best countries in the world to live in, or those who experienced the most socialist or communist governments, are all in cold climes.  people have to help each other out or they will freeze to death.

Then pausing for winter stopped sometime in the 16th century, when northern Europe was a war-torn corner of continent and peasant armies still could carry the day. 17th century with professional armies was much less hindered by seasons and the Nordic countries were no exception.

The Nordic countries are today a peaceful and prosperous corner where Sweden and Denmark has long given up trying to get hegemony over the Baltics, as both countries lost to more powerful neighbours - Russia and Germany - some 150-200 years ago. But that is really no basis to argue that weather made it so.

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