AbstractThe new field of the history of knowledge is often presented as a mere expansion of the history of science. We argue that it has a greater ambition. The re‐definition of the historiographical domain of the history of knowledge urges us to ask new questions about the boundaries, hierarchies, and mutual constitution of different types of knowledge as well as the role and assessment of failure and ignorance in making knowledge. These issues have pertinence in the current climate where expertise is increasingly questioned and authority seems to lose its ground. Illustrated with examples from recent historiography of the sixteenth to twentieth centuries, we indicate some fruitful new avenues for research in the history of knowledge. Taken together, we hope that they will show that the history of knowledge could build the expertise required by the challenges of twenty‐first century knowledge societies, just like the history of science, throughout its development as a discipline in the twentieth century, responded to the demands posed by science and society.