Liberia was always an interesting case with power alternating between the descendants of roughly 300 black American settlers - the Americo-Liberians - who had set up an independent republic in 1847. If Kenyans think the 39 years of KANU one-party rule was too much, the True Whig Party, controlled by the same incestous elite, held office from 1877 to 1980 - more than 100 years. A select few - basically a ruling aristocracy - the Barclays, the Kings, the Tubmans, and later Tolbert, lorded it over the black native Liberians, whom they regarded as a different, inferior race.
As they say, when you push folks to the corner, they're apt to push back. Hence it came as no surprise that one Master Sergeant Doe, who was what the Americo-Liberians derisively referred to as a 'country boy', easily rose to power on that night, April 12, 1980.
I will check out the book, Windy City Assassin.