This dataset provides the latitudinal distribution of biomes (reconstructed at individual pollen sites) in northern Africa today and during the mid-Holocene (6000 ±500 yr B.P.) and the maximum and minimum estimates of the increase in precipitation (ΔP) required to support grassland at each latitude. As a model benchmark, the simulated change in ΔP is required to lie above/within the ΔP required to support grassland at all latitudes from 0-23° N.