Kololo.
David Livingstone spent many years exploring present-day Zambia. His first trip was in 1851 when he reached Linyanti (on the border of present-day Namibia and Botswana). From there he travelled north and reached the Zambezi River. He was with his wife and four young children.
At Linyanti he met Sebitwane, Chief of the Kololo people:
He was upon an island with all his principle men around him engaged in singing. … He signified his joy and added ‘Your cattle are all bitten by tsetse and will definitely die; but never mind, I have oxen and will give you as many as you need.’ He presented us with an ox and a jar of honey. … Prepared skins as soft as cloth were given as a covering for the night.
Sebitwane dies while David Livingstone is at Linyanti. He comments:
He was decidedly the best specimen of a native chief I ever met.
David Livingstone, at this point, knows he needs to travel more and that he cannot take his family with him. He therefore takes them back south and sends them to England. The next time he treks to Linyanti and further is two years later …
The Kololo people are now not recognised as a tribe of Zambia. They were overthrown by the Lozi in 1864 when most of the Kololo were killed. They do, though, have a place in our tribal history as many children were born to the Kololo while they ruled the kingdom. These children have passed on the Kololo gene to many Lozi people in today’s Zambia.
Zambia's Traditional History 