Answer:
In the Middle Ages, the Catholic church was the most powerful socio-political body there was and as a result, controlled a lot of governments.
With the Protestant and Catholic Reformations, things changed. The countries of Europe saw their populations support either one or the other and so the rulers generally followed the denominations that would give them the most influence.
It also led to a decrease in the power wielded by the Catholic Church as the followers of the various denominations vied for control of their countries.
The Reformation also shaped colonial expansion in no small part as the European powers tried to spread their denominations to areas around the world so that their denomination would become the most followed as they believed this to be their responsibility.
The Spanish for instance, enforced Catholicism in all the areas they controlled and the British gave preference to Protestant movements.
