Custom is lord of all − The Bronze Age spread of the cremation custom in Northern Bronze Age by using strontium isotopes

• The earliest Bronze Age cremations of Northern Germany are non-local. • Children played an important role in the spread of the cremation burial. • First strontium isotope analyses conducted on cremated human remains from Bronze Age burial contexts in Northern Germany. • Establishment of strontium isotope-relevant baselines for Northern Germany. • High relevance to current debates on mobility, identity, and funerary change in the Bronze Age. With the aim of reconstructing the spread of cremation burials around 1300 BCE, cremation burials from Schleswig-Holstein were selected for the study. The selection was made on the basis of previous research, e.g., whether the burials were of early date and thus were among the first cremations in Schleswig-Holstein. The graves came from Albersdorf, Bornhöved, Grevenkrug, Leezen, Mang de Bargen and Nützen. The question arose as to the mobility of these people, i.e., whether they were local or non-local. The burnt bone material was sampled and analysed for strontium isotope composition. Information on the geological conditions, which is crucial for the interpretation of the results, was also compiled for Schleswig-Holstein and compared with existing research and environmental samples from Jutland and Funen, as well as samples from Schleswig (Haithabu). More data is of course needed for a reliable assessment, but these initial investigations show that the early cremations were probably non-local. Furthermore, previously published osteological analyses revealed that these individuals were often children, so it can be assumed that children played an important role in the spread of the new burial type.