The aim of this paper is to make us aware of the limits of the numismatic documentation of Northern and Eastern Europe during the Early Middle Ages/the Viking Age. The sheer mass of material – almost 900,000 coins are recorded from finds along with numerous non-monetary silver artefacts – may induce us to think that everything is documented already, but at a closer scrutiny, this turns out to be wrong. Some regions and periods and some find categories are well covered by the material, others not. The paper presents a series of cases where a new find, a new technology (e.g. metal detector), a new methodological approach (e.g. die studies) or simply a more detailed study of the material brought new and unexpected insights. Some of the cases c...