Digital history has spawned many great individual projects, and proven its value as both a methodology for the interrogation of sources and as a medium for the presentation and communication of research results. But the experiences of projects building research infrastructure for historical research raise the question of whether these methods can scale toward the realisation of historical ‘big data,’ or whether there are hindrances to this goal inherent in our current conceptualisation of the intersection between historical methods and computational ones. This paper discusses a number of the current barriers discovered by large-scale historical research infrastructure projects, including heterogeneous conceptions of what data is, hidden elements of data and the epistemics of humanities research. At the project level, these issues can be managed, but if digital history is to scale and grow to fit the infrastructural capability available to it, then a revisiting of some of the conceptual underpinnings of digital historical studies will be required.