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Abstract. Marine fronts delineate the boundary between distinct water masses and,through the advection of nutrients, are important facilitators of regionalproductivity and biodiversity. As the modern climate continues to change, themigration of frontal zones is evident, but a lack of information about theirstatus prior to instrumental records hinders future projections. Here, wecombine data from lipid biomarkers (archaeal isoprenoid glycerol dibiphytanylglycerol tetraethers and algal highly branched isoprenoids) with planktic andbenthic foraminifera assemblages to detail the biological response of themarine Arctic and polar front migrations on the North Iceland Shelf (NIS) overthe last 8 kyr. This multi-proxy approach enables us to quantify thethermal structure relating to Arctic and polar front migration and test howthis influences the corresponding changes in local pelagic productivity. Ourdata show that following an interval of Atlantic water influence, the Arcticfront and its associated high pelagic productivity migrated southeastward tothe NIS by ∼6.1 ka. Following a subsequent trend in regionalcooling, Polar Water from the East Greenland Current and the associated polarfront spread onto the NIS by ∼3.8 ka, greatly diminishinglocal algal productivity through the Little Ice Age. Within the last century,the Arctic and polar fronts have moved northward back to their currentpositions relative to the NIS and helped stimulate the productivity thatpartially supports Iceland's economy. Our Holocene records from the NISprovide analogues for how the current frontal configuration and theproductivity that it supports may change as global temperatures continue torise.