What happened in Uganda after the Buganda agreement 1900?

The Baganda immediately offered their services to the British as administrators over their recently conquered neighbours, an offer which was attractive to the economy-minded colonial administration.

Baganda agents fanned out as local tax collectors and labour organizers in areas such as Kigezi, Mbale, and, significantly, Bunyoro.

This subimperialism and Ganda cultural chauvinism were resented by the people being administered.

Baganda insisting that other tribes should learn Luganda:

Wherever they went, Baganda insisted on the exclusive use of their language, Luganda, and they planted bananas as the only proper food worth eating.

They regarded their traditional dress—long cotton gowns called kanzus—as civilized; all else was barbarian.

They also encouraged and engaged in mission work, attempting to convert locals to their form of Christianity or Islam.

In some areas, the resulting backlash aided the efforts of religious rivals—for example, Catholics won converts in areas where oppressive rule was identified with a Protestant Muganda chief.

The people of Bunyoro were particularly aggrieved, having fought the Baganda and the British; having a substantial section of their heartland annexed to Buganda as the “lost counties”, and finally having “arrogant” Baganda administrators issuing orders, collecting taxes, and forcing unpaid labour.

In 1907 the Banyoro rose in a rebellion called nyangire, or “refusing”, and succeeded in having the Baganda subimperial agents withdrawn.