European colonizers brought with them rinderpest, commonly known as cattle plague, which destroyed much of the indigenous cattle population, and jiggers, a small flea-like pest that burrows into feet, crippling the infected person and sometimes leading to gangrene. Bruce Berman and John Lonsdale, two historians specializing in Kenya’s colonial era, estimate that the Maasai community, one of the most militant groups resisting the British in East Africa, may have lost up to 40 percent of its population. The pandemics and outbreaks in that first decade of the 20th century decimated populations and made it impossible to mount any coordinated military resistance.