During the past 40,000 years global climate has moved into and out of a full glacial period, with the deglaciation marked by several millennial scale rapid climate change events. Here we investigate the ecological response of deep-sea coral communities to both glaciation and these rapid climate change events. We find that the deep-sea coral populations of Desmophyllumdianthus in both the North Atlantic and the Tasmanian Seamountsexpand at times of rapid climate change. However, during the more stable Last Glacial Maximum the coral population globally retreats to a more restricted depth range. Holocene populations show regional patterns that provide some insight into what causes these dramatic changes in population structure.The most important factors arelikely responses to climatically driven changes in productivity, [O2] and [CO32-].