North American Speyeria butterflies are a group whose species hypotheses are confounded by shared wing color patterns between sympatric populations of closely related recognized species due to a putatively recent origin in evolutionary time. Previous studies of this group and the closely related Palearctic genus Argynnis , suggest that Speyeria is monophyletic but derived from within Argynnis . Sampling in these studies has either involved few basal Speyeria species, or too few Argynnis species (Simonsen 2006, Simonsen et al. 2006). Thus, no comprehensive phylogenetic analysis exists for all members that answers the question of monophyly of Speyeria , or other subgeneric taxa,and their relationship to Argynnis species. A phylogenetic analysis was completed of all North American Speyeria species and nearly all species within Argynnis , using one mitochondrial (CO1) and four nuclear genes (EF1?, WG, GAPDH, and RPS5). The results indicate that North American Speyeria is a monophyletic group, but that Palearctic Argynnis is paraphyletic. Three major lineages are identified within Argynnis sensu lato : two Palearctic and one containing both Palearctic and Nearctic species. Argynnis species representing the subgenera Argyreus , Argyronome , Childrena , Damora , Pandoriana , and Nephargynnis , belong to a well-supported lineage that split early in the evolution of the group and is comprised of species with long branches. Fabriciana and Mesoacidalia were both recovered as strongly supported lineages, except for A. clara which was recovered as sister to Speyeria . In summary, the phylogenetic analyses suggest the need for reorganization into three genera: Argynnis , Fabriciana , and Speyeria . The results have implications for the conservation of these butterflies across the temperate zone by providing a framework for understanding potential gene flow between sympatric species complexes, proper taxonomic validity, and the natural history of threatened populations of Speyeria and Argynnis butterflies.