As a former member of Ben Hall's lab at the University of Washington, Seattle, we studied rhododendrons to better understand speciation, evolution, and biogeographic history of the group. Our lab sequenced the R. williamsianum genome from subgenus Hymenanthes, generated a chromosome-level assembly, and found two ancient whole genome duplications in the genome. We used this genome in combination with next-generation sequencing data to uncover the evolutionary relationships within subgenus Hymenanthes and section vireya to infer biogeographic histories and evolution of flower symmetry. We also examined the evolution of flower symmetry genes in sect. vireya to identify whether duplications and/or losses in these genes were associated with changes in flower symmetry.