Historic period Plains biographic art provides narratives of the deeds and actions of Indigenous peoples of the region. The Crow (Apsáalooke) are one such people with a rich record of biographic drawings in rock art and portable works. However, chronological and stylistic links between these two media have long been thought out of reach, even though such links are essential if the abundant Historic period rock art is to be fully incorporated into discussions of Apsáalooke history and their connection better ascertained to documented historical and ethnohistorical events and trends. Indeed, the lack of such a framework locks away a vast wealth of history in these hundreds of rock art pictures. In this article we present a statistical framework for comparing better-dated Crow portable artworks with their rock art equivalents. We are able to place rock art imagery from five sites into a relatively fine-grained chronological order, which permits a better understanding of changing patterns in Crow stylistic imagery. This permits a direct association with changing historical circumstances and facilitates a better understanding of the link between social history and the changing patterns seen in these artworks. Moreover, in one case, our analysis provides archaeological confirmation of Crow ethnohistory.