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Sageretia (Rhamnaceae) comprises c. 35 species of climbers and shrubs adapted to tropical and warm climates. The genus shows a disjunct distribution, with species in the Old and New Worlds. Aiming to trace the evolutionary history of Sageretia and understand its current Old-New World distribution pattern, we reconstructed phylogenetic relationships and biogeographical history of this taxon based on two nuclear (ITS, ETS) and three plastid (psbA-trnH, petA-psbJ and trnL-trnF) loci, against the backdrop of tribe Rhamneae. Phylogenetic analyses show that Sageretia is monophyletic and can be subdivided into three clades that are also supported by morphological and distributional data. Dating analyses and ancestral area reconstructions indicate that Sageretia probably originated in tropical Asia during the Eocene. Until the Miocene, it spread northwards, colonizing areas that became suitable due to the retreat of the arid belt, and it subsequently dispersed to the New World via the Beringian Land Bridge (BLB) and to Africa via Arabia. Global cooling, which began in the late Eocene, may have caused the split between the tropical Asian lineage (clade I) and its warm-range sister lineage (consisting of clades II and III), and the breaking of the BLB triggered the divergence of the warm-range lineage into Old World (clade II) and New World (clade III) lineages.