An initial study of the ¹³ C values for human bone collagen of 27 Norse Greenlanders in the late 1990s suggested a change in the Norse diet from predominantly terrestrial to predominantly marine food. This shift may well indicate a change in diet; the question left open by the limited initial isotope study was, however, whether the change in diet was a reflection of altered subsistence strategies or altered farming practices. Furthermore, the first study did not convincingly answer the question of whether the dietary change occurred gradually over time or within the space of a few years—and, if the latter case, when? Neither did it answer questions concerning dietary differences between the two Norse settlements, between individual farms and between the sexes, or the nature of the marine food that was consumed. Distinguishing locally born people from foreigners is yet another matter for investigation in order to leave out of account persons that grew up outside of Greenland. This new study includes 437 samples: 183 from humans—118 Norse and 65 Inuit—and 254 from animals. The samples are from 19 Norse sites (farms): 13 from the Eastern Settlement and 6 are from the Western Settlement. For comparison, we have also included samples from both humans and animals from 22 Inuit sites. This paper sets the scene for the new study and the following papers in this Special Volume. Former studies in Norse diet and Norse resource utilization are recapitulated, and all the Norse sites represented in the study are presented, as are all the samples included in the study. Chronology is a recurrent problem in Norse archaeology, and our focus, in particular, is on the attempt to date the samples included in the study that have not been radiocarbon dated.