The Hatfield and McCoy feud was a notorious conflict between two families in the late 19th century in the Appalachian region of the United States. The Hatfields lived in West Virginia, while the McCoys resided in Kentucky. The feud escalated over various disputes, including land ownership and personal grievances, leading to violence and several deaths. The rivalry gained national attention and became a symbol of family feuds in American history. It involved numerous skirmishes and legal battles, with both families suffering significant losses. The feud eventually subsided, but it remains a well-known story of conflict and rivalry in American folklore.