By the mid-19th century, Europeans suddenly tramping all over Africa in search of fame and fortune, even Kenya's intimidating interior was forced to give up its secrets to outsiders. European interest in Kenya focused primarily on abolishing the slave trade and discovering the source of the Nile River. This period of exploration was characterized by Europeans as the Golden Age of Exploration. Between 1840 and 1880, famous names such as Livingstone, Stanley, Burton, and Spike mapped and recorded the interior of Africa. For the first time Europeans witnessed first-hand the unique beauty of Kenya and they recorded it for history. The European governments, however, displayed no serious interest in the reports as the land appeared hostile and unproductive. At this stage, there was no incentive to occupy the newly discovered lands.


The end of the 19th century brought a change in this attitude. Bismark, the leader of Germany, expressed a desire to join his other European neighbors in securing a portion of the new land. During this period of international rivalry, often dubbed the "Scramble for Africa," the European powers all laid claim to African territories. The various claims of the nations were settled at the Berlin Conference of 1884-1885. At this time, most of the continent of Africa was divided into colonies: France claimed the majority of West Africa; Germany received much of the eastern territory that is now Tanzania; Belgium got the Congo region; Portugal retained control of Mozambique and Angola; and Britain received the remainder of the continent. Africans were not invited to attend the conference and therefore received not even an acre of their own land.


Until the 1880s, the Rift Valley and the Aberdare highlands remained the heartland of the proud warrior tribe, the Maasai. By the late 19th century, Maasai began to crack because of years of brutal war between the ilmaasai and iloikop groups and the simultaneous arrival of rinderpest (a cattle disease), cholera, smallpox and famine. For the reason, the British were able to negotiate a treaty with Olonana (known today as Lenana), The Laidon (chief or spiritual leader) of the Maasai, allowing them to march the Mombasa-Uganda railway line right through the heart of the Maasai grazing lands. The halfway point of this railway is roughly where Nairobi stands today.