The first Europeans to Uganda were the explorers and Christian missionaries. John Hanning Speke (1861-1863), Sir Samuel and Florence Baker(1863-1864), Henry Morton Stanley  and his Emin Relief Expedition (1888-1889) and Frederick Lugard (1890-1891). Upon their arrival, they found already established central systems of governance in form of kingdoms notably Buganda, Bunyoro, Ankole and Toro with kings at the helm of hierarchy. Although other kingdoms also did exist, these kingdoms shaped the state of Uganda’s affairs decades ago and helped in penning her political history. Whereas the explorers went about in earnest exploration and made great discoveries – Speke discovered the source of the Nile, and Samuel and Florence Baker lake Albert which he named after Albert prince consul of Britain and was Knighted in reward, the missionaries  who were Anglophile Protestants and Francophile Catholics pitched camp in Buganda kingdom where they were welcomed and embarked on winning converts to the Christian faith.
Bunyoro Kingdom under Kaberega was suspicious of foreigners and at his court, they were not welcome. Kaberega’s recalcitrance set him against the white man from the outset. Although the white man was previously welcome in Bunyoro under Omukama Kamurasi for in 1862, Kamurasi’s court welcomed Speke and Grant the first Europeans to reach Bunyoro, and two years later the Bakers  who entered Bunyoro and spent a year. When Omukama Kamurasi died in 1869 and Kabarega ascended the throne after a protracted six- month battle, this changed. Regarded as the greatest of all Bunyoro’s rulers and were it not for the British intervention, would surely have not only restored his Kingdom to it’s former glorious self which internal instability propagated by rebellious princes had robbed it of but taken it to even far more greater glory.

The missionaries at Mutesa’s court unlike the explorers whose efforts were recognized and appreciated, had theirs antagonize the Swahili Arab traders who were also busy making muslims of the natives having arrived earlier in the mid 19th century from the east coast and already resident at Mutesa’s court with his permission to operate from his capital. The Arabs had besides locals, converted several Baganda clan chiefs to Islam.
Upon Mutesa’s death in 1884 the kingdom was turned into a hotbed of religious rivalry that was only aggravated by his successor and son Mwanga who was unlike his father. Muslim leaning, he in 1885 under the influence of a moslem advisor ordered the execution of Bishop Hannington together with 50 christians many of whom were roasted to death on a spit. Then he shifted allegiancies from the moslems to the traditional Baganda chiefs who in turn offered to help him expel all converts of the three faiths from the kingdom. Threatened, Muslims and Christians combined forces and launched a successful attack on the throne and overthrew Mwanga in 1888. However, their hopes in a brighter tomorrow came to nought for Mwanga’s Muslim- backed successor was even
worse and his relentless persecution of Christians climaxed to a civil war in 1889 between Christian and Muslim factions and led to the expulsion of muslims from the capital Kiwewa inclusive. These later joined forces with Kabarega of Bunyoro.
Mwanga was then reinstated as Kabaka and with the muslims safely out of the way, the rivalry between the European powers so eager to possess fertile, well- watered and central Buganda escalated into open rivalry between the Christian factions. When Carl Peters of the German East Africa Company arrived in Mengo in 1890 with a treaty, a relieved Mwanga signed it possibly with the hope that German involvement would help end the rivalry between the Christian factions but this was not to be for the German exchanged Buganda with Heligoland a strategic North Sea Island which was in the possession of the British.
The British East Africa Company then assumed possession of Buganda, setting the stage for colonization. However, the absolute powers of the monarchy and the interests of the colonialists conflicted consequentially in 1890 when the Kabaka Mwanga who had yet again shifted allegiences ruled arbitrarily in a murder case by acquitting a catholic who was accused of killing a protestant on a plea of self defense. Captain Lugard of the BEA Co angered by this and Mwanga’s refusal to have him retry the man drove Mwanga and his catholic supporters to an Island on Lake Victoria and later with troops routed him from the Island. Mwanga fled to Bukoba in Tanzania but returned to his Kingdom and signed a treaty recognizing the company’s authority in his Kingdom. Consequently, Lugard returned to Britain and rallied public support for the colonization of Buganda and although he was met with stiff opposition by the liberal government then under Gladstone which was opposed to the acquisition of more territories, his efforts were nevertheless fruitful and culminated into the appointment and dispatch of Sir Gerald Portal as a commissioner advisor on the future policy on Buganda.

When Portal arrived in Kampala in 1893, he was met greeted by a flood of petitions from all quarters but the missionaries collectively felt that colonization would further their interests in the kingdom. Persuaded thus, portal raised the Union Jack in April of that year and in March signed a treaty with a resigned Mwanga offering British protectorship over Buganda and in exchange, Britain had the right to collect and spend taxes.