Expansion of crops beyond their centres of domestication is a defining feature of the current Anthropocene Epoch. These patterns have been quantified at large spatial scales, but the drivers and consequences of change in crop diversity and biogeography at national-scales remains less explored. We use production data on 339 crops, grown in over 150 countries from 1961–2017, to quantify changes in country-level crop richness and evenness. Virtually all countries globally have experienced significant increases in crop richness since 1961, with the early 1980s marking a clear onset of a ~ 9 year period of increase in crop richness worldwide. While these changes have increased the similarity of diversity of croplands among countries, only half of countries experienced increases in crop evenness through time. Ubiquitous increases in crop richness within nearly all countries between 1980–2000 are a unique biogeographical feature of the Anthropocene. At the same time, opposite changes in crop evenness, and only modest signatures of increased homogenization of croplands among countries, underscores that the understanding or predicting of consequences of crop diversity change requires context-dependent and, at least, national-scale assessments.