Haiti, one of the least culturally diverse countries in the world in 2013
Based on a study done on more than 180 countries, it was concluded that Argentina, Haiti or the isolated Comoros islands off the southeast coast of Africa are the countries least culturally diverse.
On the other hand, countries like Chad and Togo, with more than 37 tribal groups that speak more than 39 languages and where the various groups did not share common culture or history were most culturally diverse.
Argentina, the Comoros, Haiti, the Dominican Republic, Rwanda and Uruguay rank as the world's least diverse countries
A caution: Cultural diversity is a different concept than ethnic diversity