How does a country go about changing its' name? What process is involved and how much time could it possibly take?

There are too many instances when this has occurred. Each had their own circumstances and procedures.

Here is what is probably an incomplete listing . Most of the former Colonial territories have had at least one name change (especially in Africa) .

List of country name etymologies - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/List_of_country_name_etymologies)