The Arctic Ocean is presently experiencing large amplitude changes with profound consequences for the cryosphere. However, the fate of the Arctic realm, including land and ocean, has very large uncertainties, with possible retroactions at large subcontinental to global scales. In this context, the knowledge of the Arctic history at time scales encompassing the Pliocene to the present could help narrow uncertainties. Despite difficulties in accessing the Arctic and the setting of the chronostratigraphic framework, new developments in geochronology, proxy data acquisition and numerical modelling may help to revise the paleoclimate history of the Arctic Ocean. We thus think that an update on the status of the Arctic Ocean in the paleoclimate system is timely. In this session, we invite contributions on the evolution and changes in the Arctic realm from several perspectives, including stratigraphy, palaeogeography, palaeoclimatology, paleoceanography, and palaeoecology, using proxy data and/or model simulations