The discipline of history, probably more than the other disciplines in the humanities, has had to struggle with the postmodern challenge. After a necessarily short and simplified overview of the various thoughts on the impact postmodernism has had upon the historical discipline, this paper addresses a problem rarely raised in the philosophy of history, but which has been set out with a renewed acuteness by postmodernism: not the practical, but the theoretical and discursive relation historians have with their own knowledge, i.e. the epistemological exercise. I argue that while, for a long time, historians have applauded the epistemological exercise’s absence in their discipline, the postmodern challenge has led many of them to object to it. It is indeed the way historians relate to epistemology that has been deflected under the impulse of postmodernism. Beyond this major discursive deflection, I conclude that it would be relevant to reflect further on the purposes and the ends of the epistemology within the historical discipline. This reflection, in turn, invites us to rethink the old and thorny question of the fraught relationship between history and philosophy.