Digital maps and a dated supertree of global carnivore species were used to assess the distribution of American carnivores' phylogenetic diversity (PD, measured in millions of years) both from a geopolitical perspective (‘evolutionary heritage’ or EH) and on the basis of species' range size and conservation status. A new measure, range-weighted EH, is introduced. This measure partitions the total PD of the tree between countries based on the proportion of species' ranges within each country. Sociopolitical correlates of these measures were explored. Only 3% of the total PD in the Americas is endemic to any one country. As expected, the measures of PD are positively correlated with each other and with species richness. The USA contains the most species, the most EH and the second most range-weighted EH after Brazil. Indeed, larger and richer countries, and those with the lowest state-corruption-rate hold most EH. No significant differences were observed in the amount of PD remaining if species are removed at random, or following more plausible sequences based on IUCN conservation status and range size. Eighty percent of the American carnivores' PD would remain safe if only the set of not threatened species were to remain. Roughly the same is true if only the 50% most widespread species were to persist. Samples of wide-ranging species represent more of the entire tree than do samples of narrow-ranging species, highlighting the importance of the former for conservation strategies. We suggest that similar approaches be applied to more groups across the globe to assess which countries and areas steward the most PD, as well as which species and taxa do, in order to plan conservation actions consequently.