During the late 19th and early 20th centuries, European colonial powers divided Africa into various colonies. In 1885, the Berlin Conference led to the establishment of boundaries that divided Maasailand between British Kenya and German Tanganyika (now Tanzania). As a result, the Maasai lost a significant portion of their pre-colonial lands, with estimates suggesting around 60% of their territory was lost. They were increasingly confined to drier areas with less reliable rainfall and poorer pastures.

Colonial authorities also converted large portions of Maasai grazing lands into game reserves and national parks, such as the Maasai Mara and Serengeti. The Maasai were restricted from entering these reserves, which further limited their access to traditional grazing grounds. While these restrictions were intended to protect wildlife, they had significant adverse effects on the Maasai, including challenges related to drought and changes in their social structure. The policies also led to the reduction of their cattle herds due to limited access to grazing land.