There's a very brave, honorable politician, who unfortunately was lost in the annals of history, as a man directly responsible for Russian support during the civil war.
Ali's grandfather specifically named his son after Cassius to honor Cassius, the KY politician. The son proceeded to do the same, with who would eventually be a famous boxer, M. Ali.
The boxer changed his name to Ali, both due to his conversion to islam , and because he was angry to take the name of a plantation owner.
The latter is true - Cassius was a plantation owner. However, early on he defender ardently emancipation. He in fact suffered multiple murder attempts from actual slavery advocates... who surrounded him in KY