We obtained stable isotope signatures (δ 1 3 C, δ 1 5 N) and AMS radiocarbon dates for a small set of Dorset remains, Thule-era burials from northwest Hudson Bay and proto-historic burials from Southampton Island to assess the importance of whaling in eastern Canadian Arctic economies. Classic Thule occupation of the Eastern Arctic (ca. AD 1000-1350) coincided with the Medieval Warm Period and was thought to have been facilitated by dog traction and open-sea hunting of bowhead whale. Despite the potential economic importance of whaling, dietary reconstructions for this period are based on the relative frequency of common prey types in midden faunal assemblages and rarely include bowhead whale skeletal elements, which often comprise the superstructure of Classic Thule residential dwellings. Although our findings are constrained by the paucity of Classic Thule burials at sites under study, they provide an empirically derived estimate of reliance on whaling for the Modified Thule, those who post-date AD 1350, indicating whaling accounted for approximately 12% of dietary intake. We also examine the relationship between Thule whaling and indicators of status and identify a Dorset-aged burial and three individuals with European diets among the proto-historic collection from Southampton Island.