All societies are ruled by their lighter skinned members, including Negro African and Dravidian South Asian societies. This is not a racist statement but rather fact. When a dark skinned man in a generally dark skinned tribe usurps the rulership of the lighter skinned king, he then marries a relatively light skinned woman or takes one or more such as extra wives or concubines. He marries his children to lighter skinned mates. This is not racism as such because they are all of the same genetic heritage. It is definitely a skin tone bias and it is universal. Even in the blackest of dravidian families mom and dad are apt to ask of their daughter, “Isn’t he a bit dark?”
Those rulers you're talking about are darker-skinned, so maybe what you mean is the lighter-skinned have higher status. "Usurpers" may convey the wrong impression too.
Anyway, this is something that happens in Mexico too. Darker-skinned politicians generally take wives from the lighter-skinned social elites.
FWIW: Butterfield probably would have started out in segregated schools and went on to a historically Black college in the area, so if he didn't want to move, he'd most likely be considered Black by his neighbors.