Here's the history as the Institute has it on its website
The key to understanding the development of the Frankfurt School is to understand some of the history of the social sciences. The Frankfurt School had as its mandate the scientific study of society and culture. Recall the earlier discussion on the nature of the social sciences. This now needs to be expanded.
The earlier discussion established that studying humans, either individually or in groups, could not proceed in the same way that the natural sciences proceeded. We might be able to explain the natural world, in the sense of finding causal connections, but we needed to understand the human world.
When the Frankfurt School was being built in the 1920s, the state of the social sciences was fairly rudimentary. That does not mean that people hadn't been asking about how to understand the social world - that had been true since the times of Plato. But as disciplines within the university, the social sciences were recent.
The Frankfurt School describes a range of projects and movements at different times. Douglas Kellner gives a good overview:
It is thus impossible to characterize the Frankfurt School as a whole, since their work spanned several decades and involved a variety of thinkers who later engaged in sharp debates with one another. Rather one should perceive various phases of institute work. (1) the empirical-historical studies of the Grunberg era. (2) attempts in the early to mid-1930s to establish a materialist interdisciplinary social theory under Horkheimer’s directorship. (3) attempts to develop a critical theory of society during the exile period from about 1937 to the early 1940s. (4) the dispersion of institute members in the 1940s and new directions sketched out by Adorno and Horkheimer in Dialectic of Enlightenment. (5) the return of the institute to Germany and its work in Frankfurt during the 1950s and 1960s. (6) the development of critical theory in various ways by Fromm, Lowenthal, Marcuse and others who remained in the USA. (7) the continuation of institute projects and development of critical theory in Germany by Jürgen Habermas, Oskar Negt, Alfred Schmidt, and others in the 1970s and 1980s. (8) contributions to critical theory by younger theorists and scholars currently active in Europe and the USA. Douglas Kellner, "Frankfurt School", at http://www.gseis.ucla.edu/faculty/kellner |