I think the two people most responsible for the feud were Jim Vance on the Hatfield side and Perry Cline on the McCoy side. The murder of Asa Harmon McCoy did not really start the feud, because there were no attempts at retaliation by the McCoys and no further conflict between the families for over a decade. Also, there was speculation that Vance killed Harmon, but no proof. While there were probably still bad feelings between the families, the feud really started when Perry Cline tried to swindle Anse Hatfield out of his land. Unlike this show, the case went to court and Anse was awarded the 5000 acres from Cline. A few months later, the pig incident happened and then things snowballed.
They DID include Perry/Anse's court case in the miniseries. They just had someone mention it in one sentence after it happened and moved on.
That's what ppl like Cline/Kline do. He was not white , neither was he a Christian.
"Stalingrad. . . The fall of Stalingrad was the end of Europe. There's been a cataclysm."