The compilation of a global phylogenomic and distributional dataset of brittle-stars is used to improve our knowledge of the distribution and evolution of deep-sea life. Our team has produced a 2800-sample robust, comprehensive, fossil-calibrated phylogeny of the group based on 275 kb of nDNA and 1.4 kb mtDNA COI sequences. Here I present a global marine biogeography from this data, showing the evolutionary relationships between 37 biomes, across 3 depth strata (shelf, bathyal, abyssal) and all oceans, analyzed using multivariate statistics on a novel phylodiversity index, and Markov-k models of discrete character (biome) evolution. The shelf has the greatest range of phylodiversity, with tropical, temperate, and polar biomes forming distinct clusters. The temperate shelf faunas have evolved independently from tropical faunas over the past 50 my, whereas polar shelf faunas are more closely related to bathyal faunas. The bathyal and abyssal faunas have reduced variability and are much more connected over evolutionary time. In particular, many temperate bathyal species or lineages have achieved widespread distributions, crossing the tropics on the eastern side of the Atlantic and Pacific Oceans. The overall impression is one of historical and ongoing interchange of deep-sea biodiversity across the marine realm.