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Deglacial relative sea-level (RSL) data provide important constraints to Glacial Isostatic Adjustment (GIA) models because they record the vertical land deformation and gravity field change history since the Last Glacial Maximum (LGM). Although the Russian Arctic is an essential region for the study of GIA because it was covered by the large Eurasian ice sheet at LGM, few GIA studies have been conducted due to the lack of high-quality RSL data. Here we use a recently-released quality-controlled RSL database from the Russian Arctic (Baranskaya et al., 2018) to validate the latest iterations of 1D models ICE-6G_C (VM5a) (Peltier et al., 2015) and ICE-7G_NA (VM7) (Roy & Peltier, 2017) and new 3D GIA models. 3D models have the potential to better fit the deglacial RSL data because surface geology and seismic tomography reveal that the Earth should be 3D. The Russian Arctic database consists of > 350 sea-level index points (SLIPs) from indicators such as isolation basins, raised beaches and marine terraces, and deltaic salt marshes (laidas) which estimate the unique position of RSL in space and time with an associated uncertainty. In addition, there are > 150 limiting data that contain the upper and lower limits of RSL. The marine limiting dates are from in situ marine mollusc shells or sediments containing marine diatoms and foraminifera, whereas the terrestrial limiting dates are from autochthonous freshwater peat, as well as alluvial, lacustrine, and aeolian deposits. We subdivide the Russian Arctic database into 24 regions. The regions illustrate three contrasting deglacial RSL trends: (1) Rapid RSL fall in the western Russian Arctic (e.g., Barents and White seas, Franz-Josef-Land) during the Holocene due to the deglaciation of the Eurasian ice sheet complex (Regions 1-19); (2) Monotonic RSL rise in the central Russian Arctic along the Timan coast and Kara Sea shelf due to proglacial forebulge collapse (Regions 20-21); and (3) Deglacial RSL rise in the eastern Russian Arctic with a mid-Holocene highstand from the Laptev Sea and the New Siberian islands (Regions 22-24). In the regions of falling deglacial RSL, the 1D models predictions correspond to the falling Holocene RSL data, in particular along the south coast of Barents Sea and in Franz-Josef-Land, but show notable misfits (>50 m at 10 ka BP) with the White Sea data, where most SLIPs are concentrated and therefore the deglacial RSL history are well constrained. We find 3D model predictions can significantly improve the fits around the White Sea region while retaining the comparable fits in other regions of the western Russian Arctic. In the regions of rising deglacial RSL in the central and eastern Russian Arctic, although few RSL data are available, both 1D and 3D model predictions generally fit the RSL data. Our RSL sensitivity results reveal: (1) RSL in the western Russian Arctic is sensitive to laterally varying lithosphere and 3D viscosity structure in the upper mantle; and (2) RSL in the whole Russian Arctic is less sensitive to 3D viscosity structure in the lower mantle compared to the upper mantle. Our results imply the deglaciation history of ICE-6G_C/ICE-7G_NA in the Russian Arctic requires revision, unsurprisingly since there had previously not existed data that could be invoked to constrain it, and further RSL data are needed from the central and eastern Russian Arctic to further refine both the ice and earth components of the model.