Berlinia is here enumerated as comprising 20 species, of which four were discovered and described during the course of the study. The existence of another new species is postulated. Red data assessments made according to IUCN categories show that ten species qualify for a category of threat, eight are Vulnerable, one is Endangered and one is Critically Endangered. The genus is almost exclusively west and west-central African, with a centre of diversity in coastal Gabon. A single species is confined to coastal East Africa. Typically, Berlinia species are trees of lowland forest including swamp and gallery forest formations. Separate phylogenetic analyses of nucleotide sequence data from the trnL region and psbA-trnH regions of the chloroplast confirmed that Berlinia was a member of tribe Macrolobieae and combined analyses of the two regions showed Isoberlinia and Anthonotha to be its closest relatives. Berlinia species were placed into two major clades. One clade contained species better able to tolerate relatively dry conditions than the other, had longer branches, was better resolved and better supported than the other clade, which was composed of eight of the ten most hygrophilous species in the genus, and had shorter branches with poor resolution. The short branches of the “wetter clade” indicate a significant proportion of Berlinia diversity is of recent (Pleistocene) origin. ITS data indicated that B. confusa as currently circumscribed may be a polyphyletic assemblage of two or more cryptic species. Within the long-branched clade, B. orientalis, the sole east African species was sister to the remaining species and may be a relic of a previous continuous west-east forest cover which was disrupted by the late Miocene aridification of Africa that followed the closure of the Tethys Sea, and the subsequent uplift of the central African Plateau.