It was founded in the 1970s in Berlin at the Freie Universität Berlin[?], the German branch of critical psychology predates and has developed largely separately from the rest of the field. Critical psychology is not really an division of psychology; it follows its own methodology. It tries to reformulate traditional psychology on an unorthodox Marxistic base. The appeal of critical psychology to socialists is that it is an attempt to come to grips with the social and the historical "conditionality" of human beings. One of the most important books in the field is the Grundlegung der Psychologie (Foundations of Psychology) by Klaus Holzkamp[?] (Frankfurt a. M. 1983), who might be considered the theoretical head of critical psychology.
A couple of years ago the department of critical psychology at the FU-Berlin was closed and was added to the traditional psychology department. Nevertheless, this approach of psychology is still alive.
Like many critical applications, critical psychology has expanded beyond Marist roots to benefit from other critical approaches. Consider ecopsychology and transpersonal psychology.