Well that is what will happen.. one part of the world will get a more temperate climate and at the same time, quite literally, kill people in warmer parts of the world who contributed a lot less to the problem.
I know you didn't mean it that way but...lots of people will die and it is not funny.
Vikings killed even before the advent of industrialisation and when the temperatures were below freezing most of the time in the year (it still is for many Europeans and Canadians).
I dont think the killing part is a function of mean surface temp change.
My sense is that there will be a lot more killings when global poverty rates increase from unavailability of cheap reliable energy.
I know you didn't mean it that way but...lots of people will die and it is not funny.