He later became paramount chief of an expansive region of Kenya and Uganda at the beginning of British imposition of colonial rule in East Africa.

This regazetement led to the eventual loss of political relevance of the Wanga Kingdom, although Nabongo Mumia remained a powerful and influential figure until his death in 1949.

He grew up as an ordinary Wanga child participating in domestic animal herding, farming, hunting and gathering and his most notable achievement was killing a lion and leopard by the time he was 18 years old.

His physique of being thin, having a deep voice and his shyness towards strangers made his father Nabongo Wamukoya repeatedly loath him for being an unlikely candidate for the Nabongoship (kingship).

[3] This made Nabongo Mumia King by circumstance as opposed to the tradition of kingdom inheritance based on clan members who are in line of succession.

[3][8] The Arabs were able to capture slaves from the Luo and Bukusu by directly participating in fighting enemies of the Wanga Kingdom.

Around 1890, when Fredick Lugard met Nabongo Mumia, he observed that he spoke pretty good Swahili and the larger Wanga community had Islamic regalia and demeanour.

[2] This victory made Nabongo Mumia a legend among the Abaluya, communities that were conquered and larger Kenya to this day.

This was at a time when poverty levels were exacerbated, and his individual economic might was non-comparable to many in East Africa while supporting a huge polygamous family.

[11][12] Because Nabongo Mumia was illiterate, he failed to lead the kingdom in making changes and adapting to new political developments in regard to technicalities of the administration.

[5] An action that was repeated by Jomo Kenyatta years later when he moved to England with similar concerns and fears, but eventually persuasively achieved diplomatic agreements that contributed in him being later the first president of Kenya at independence.

[13][14][15] Despite cognisance of his floundering influence and that of the Wanga Kingdom, Nabongo Mumia remained fiercely loyal to the colonial administration until his death.

[6] When Mumia died in 1949 of old age,[3] major high-ranking members of the colonial administration such as Philip Mitchell were in attendance.