Rujumbura was never part of short-lived Mpororo kingdom
In the beginning
Bantu people are believed to have left Nigeria/Cameroon border on massive and gradual migration about the time of Christ (R. W. July 1998). They entered the great lakes region about 2-3000 years ago. They entered Uganda through south west and/ or western corner. So they are the indigenous occupants of Rujumbura County (remnants of Bambuti are believed by some researchers to be Bantu people who adapted to a forest environment).
Bantu people brought with them short horn cattle, goats, sheep, poultry, crops and knowledge of iron technology (R. O. Collins 2006 & R. Oliver and G. Mathew vol. I 1963). They settled in good areas endowed with fertile and grazing land and iron ore. With iron technology (axes, machetes and hoes), they cleared land and grew a wide range of crops including bananas, grazed animals and manufactured a wide range of products based on resource endowment. They supplemented cultivated foodstuffs with plentiful wild game and fish, fruits and vegetables.