We inferred the phylogeny and historical biogeography of Parnassiinae species from the western Palaearctic using 825 bp DNA sequence from the mitochondrial protein-coding gene cytochrome oxidase I. Investigation of genetic variation revealed several cases of overlap in extent of divergence between traditionally applied taxonomic ranks. In particular, we found deep divergences between populations of Archon apollinus (Herbst) from Turkey and Israel, Zerynthia rumina (Linnaeus) from Spain and North Africa, Zerynthia polyxena (Denis & Schiffermüller) from Italy and other parts of its range, and Hypermnestra helios (Nickerl) from Iran and Central Asia. Due to incomplete sampling and weak morphological support, we only report the possibility of more than one species within each of these four taxa. The origin of ancestral Archon and Allancastria/Zerynthia is found to lie in the Iranian region. Diversification within genera is postulated to be the result of complex tectonic interactions between Eurasia and Africa during the past 20 million years, involving multiple dispersal and vicariance events.