The term 'Warrior Kaffir' is a reference to the Impi, a Zulu warrior regiment. The Impi were a military force of the Zulu nation in South Africa, and were known for their bravery and skill in battle. They were also renowned for their distinctive dress and weapons, which included spears, shields, and clubs. The Impi were an integral part of the Zulu nation's military strategy, and played a major role in the Anglo-Zulu War of 1879.