Why are redheads called gingers?

The term "ginger" isn't toward the colour but toward the temperment that was linked to those who are red haired. It was beleived long ago that those who had red hair were 'hot blooded' ill-tempered, easily angered and above all had a very large sex drive. The term Gingerism meant this, and was shortened to 'gingers' for a term toward them.