The genus was erected by the French naturalist Bernard Germain de Lacépède in 1799 with the red kite as the type species.

[3] The genus Milvus has in the past been placed in the subfamily Milvinae but molecular phylogenetic studies have shown that such a grouping is polyphyletic for Buteoninae.

[7] Successful hybridization between Milvus kites is fairly commonplace, making mtDNA analyses unreliable to resolve the genus' phylogeny.

Furthermore, there is no good correlation between molecular characters and biogeography and morphology in the red kite due to very incomplete lineage sorting.

The status of the Cape Verde kite is in doubt; while not a completely monophyletic lineage according to mtDNA data,[8] it is still best regarded as a distinct species.