Nowadays, university rankings are a familiar phenomenon in higher education all over the world. But how did rankings achieve this status? To address this question, we bring in a historical-sociological perspective and conceptualize rankings as a phenomenon in history. We focus on the United States and identify the emergence of a specific understanding of "organizational performance" in the postwar decades. We argue that the advent of this understanding constituted a discursive shift, which was made possible--most notably but not solely--by the rise of functionalism to the status of a dominant intellectual paradigm. The shift crystallized in the rankings of graduate departments, which were commissioned by the National Science Foundation and produced by the American Council on Education (ACE) in 1966 and 1970. Throughout the 1970s, social scientists became increasingly more interested in the methods and merits of ranking higher education institutions, in which they would explicitly refer to the ACE rankings. This was accompanied by a growing recognition, already in the 1970s, that rankings had a place and purpose in the higher education "system"--a trend that has continued into the present day.