OK Finn - if you want I'll assemble the colonial history of Africa - how it was pillaged for slaves then resources, broken up into countries with boundaries that reflected nothing of the ethnic makeup, tribal animosities or history of those regions.
Then subject them to colonial government aimed only at promoting the wealth and development of the colonisers - then when the shame got too much the legal slave trade was stopped (some places sooner than others) while indigenous peoples continued to subjugated, oppressed 0r used as pawns in power struggles. Just a few centuries of social destruction - then the colonisers pull out and can't understand why everything isn't roses after a few decades?
In South Africa the political colonisation didn't end until 1994. They've only had universal suffrage for two decades in a place where 'institutions' (to me the keystones of a successful democracy) were the agents of oppression, and in many ways haven't fully transitioned from that.
But lets not look at the causes, lets just look at the numbers shall we?
Click on the little diamond next to rate.
Oh look 8 of the top 10 countries are in the Americas and are former colonies.
Oh and look former colony USA has a higher homicide rate than former colony Burundi.
I won't even go into how repulsive I find the proposal that a society's woes are caused by the colour of its citizens' skins.
I hope I've met your request adequately.