Pedigree data from 11 267 animals born between 1960 and 2004 were used to analyse population structure and genetic variability of the Holstein–Friesian population in Kenya. Parameters estimated were the pedigree completeness index, average inbreeding coefficient, number of founders, effective number of founders and ancestors, and genetically important herds. The hierarchy of registered herds and concentration of origin of individuals was also assessed. Pedigree completeness of the reference population was 67.1 percent. Average inbreeding level for the entire population was 0.09 and 1.7 percent among individuals with three complete generations, and 9.2 percent among inbred individuals. Inbreeding level increased with generation from 0.8 to 2.5 percent in the most recent generation among individuals with three complete generations. Effective number of founders and ancestors were 156 and 108, respectively. The ten ancestors with the largest marginal genetic contribution accounted for 19.52 percent of the total variation. The effective number of genetically important herds that contributed breeding males to the population was 5.2. Higher levels of inbreeding were detected among individuals with at least three complete generations. Few herds contributed breeding males, causing structural weakness to the breeding programme. Recruitment of herds into the breeding tier is needed to strengthen the breeding structure and pedigree recording enhanced to enable long-term management of genetic variability.