Different types of uncertainties occur in almost all datasets and are an inherent property of data across different academic disciplines, including digital humanities (DH). In this paper, we address, demonstrate and analyse spatio-temporal uncertainties in a non-standard German legacy dataset in a DH context. Although the data collection is primarily a linguistic resource, it contains a wealth of additional, comprehensive information, such as location and temporal detail. The addressed uncertainties have manifested because of a variety of reasons, and partly also because of decades of data transformation processes. We here propose our own taxonomy for capturing and classifying the various uncertainties, and show with numerous examples how the remedying but also re-introduction of uncertainties affects DH practices.Informatics 2019, 6, 34 2 of 29 with from the point of view of risk assessment, measurements of uncertainty or methods of removing uncertainty to attain higher degrees of certainty (cf. [12]).In this context, a distinction can be made in how uncertainty is dealt with, for example, in the fields of natural sciences in contrast to the humanities. Whilst uncertainties in natural sciences are mostly related to the expected limits in the possibilities of making measurements and also inherent to the statistical properties of what can be inferred on the empirical samples, uncertainties in the humanities, however, can also involve subjective aspects related to perception, ambiguity, vagueness, incompleteness, credibility, etc.The research purpose of the present paper thus evolves out of the uniqueness of the legacy collection dealt with here. The types of uncertainties encountered in humanities datasets already differ from those more typical in the natural sciences. Our specific non-standard dataset, and the focus on spatio-temporal aspects, makes it a necessity to devise our own taxonomy in order to fully capture the relevant uncertainties.The paper is thus structured as follows: Section 1 (Introduction) presents an overview of existing and relevant taxonomies dealing with one or more of the aspects (temporal, spatial, uncertainties) central to the research purpose, and also an outline of the diverse contexts that uncertainty has been dealt with in the digital humanities field. In Section 2 (Materials and Methods), the specific dataset is illustrated, followed by a pointer to previous analyses of spatial and temporal aspects. In addition, the methods of devising our taxonomy are outlined. Section 3 (Results) presents the DBÖ (Datenbank der bairischen Mundarten in Österreich/Database of Bavarian Dialects in Austria) taxonomy of uncertainties illustrated with detailed examples of its specific categories. Finally, Section 4 (Discussion/Conclusion) discusses the newly composed taxonomy against the background of existing taxonomies that have been reviewed in Section 1. Aside from this, reflections on how the remedying or re-introduction of uncertainties affects digital humanities (DH) practice are provided.