Concepts can have a powerful public impact. The concept of post-traumatic stress disorder (PTSD) was coined fifty years ago and since then it has become a central concept in the mental health sciences. This is evident from the number of publications in psychology, psychiatry, and neuroscience. New terms and concepts naturally have their intellectual midwives, and this also applies to the consequences of traumatic stress. Initially, these midwife personnel were those who worked therapeutically with US Vietnam War veterans. Many of the latter had returned from the Vietnam War between 1963 and 1975 with psychological wounds, and it was essential to recognize and treat them appropriately. There was then a second group of midwives: Once it was officially recognized as a diagnosis in 1980, the new concept of traumatic stress was quickly embraced by the Women’s Liberation Movement. It became an invaluable resource for countless victims of sexualized and domestic violence. It soon became apparent that trauma constellations in civilian life were far more common than those of war veterans and represented the vast majority of cases.Footnote ¹

This book builds on the numerous research projects that have developed in the meantime. Since the introduction of PTSD, virtually overnight large specialist societies of scientists have been founded in rapid succession, making traumatic stress in all its phenomena and levels of impact the target of their research. The International Society for Traumatic Stress Studies was founded in the USA in 1985, followed a few years later by corresponding associations in Europe, Asia, and South America. Since its inception, the traumatic stress paradigm has attracted tens of thousands of clinicians, scientists, and scholars who have utilized it in their respective fields. It is therefore unsurprising that this paradigm, which has undergone a significant boom, has sometimes been the subject of criticism. Notable authors such as Didier Fassin and Richard Rechtman have offered critiques of this phenomenon, labeling it the “Empire of Trauma.” In similar vein, other authors have referred to the phenomenon as a “trauma industry,” a term that suggests a profit-generating business for those involved in its operations.Footnote ²

In my view, the distinction between PTSD and other psychological conditions represents a significant advance in the field of psychology. The psychological changes that people can exhibit after traumatic experiences are not depression or personality disorders, and they require different interventions. The new psychological treatments developed for PTSD have become so important globally that they are now considered essential for assisting recovery from PTSD. Prior to the advent of these novel PTSD treatments, it was exceedingly challenging to address effectively the pervasive and distressing olfactory memories associated with the acrid scent of human flesh on battlegrounds, as well as the profound and visceral fears of horror, revulsion, and destruction that often resurface in individuals who have experienced sexual assault. This book is predicated on a scientifically informed and empirically validated understanding of the tangible progress that has been made in the field of psychotraumatology, which has been shaped by a multitude of conceptual and intervention-based developments.Footnote ³

The public and other academic disciplines have readily adopted the terms and some of the detailed knowledge that has now accumulated in trauma research. This begins with concepts such as “traumatic flashbacks,” “traumatic grief,” “child abuse,” “family violence,” and “trauma survivor,” all of which have become exponentially more frequently used terms over the last few decades. Additionally, the field encompasses terms such as transgenerational and intergenerational transmission (which are essentially synonymous), resilience (a rapidly expanding field), and post-traumatic growth, which are new discourse terms and scientific fields that examine family histories and societal influences. It is evident that there is a connection between these terms and the concept of historical trauma, which emerged around the turn of the millennium. I will address this in more detail below.

Let me begin by discussing the science underlying this book and its methodological approach. This involves two problems. First, how can the enormous wealth of very different types of relevant scientific results be organized and presented? Second, because the topic of this book is linked to a committed empowerment approach, how can the interaction of commitment and scientific claim be taken into account?

Coupled Scoping Reviews

This book will examine the approaches used in psychology, psychiatry, and the social sciences. It will present and analyze specific concepts and their empirical status to assess their scientific fruitfulness. The method of scoping reviews has emerged for completely new and developing fields of research. This method is defined by first determining the scope of the topic, examining the relevance of content areas, and compiling a primary “body of knowledge” by scanning and selecting topics that were often previously unconnected. The scoping review method allows initial conclusions to be drawn regarding the potential of a new scientific topic and the areas that require further investigation. This modus operandi is also pertinent to the subject matter of this book, which encompasses a diverse range of fields, including humanities approaches such as hermeneutics and argumentative reasoning, qualitative social research such as ethnographies and grounded theory, and, most broadly represented in this book, quantitative research using small or very large amounts of data. The disciplines that will be represented include psychology and psychiatry, social work science, sociology, political science, demoscopy (study of public opinion), area or regional studies, ethnology, empirical legal studies, and, of course, history. In my view, all of these disciplines are indispensable when it comes to the topic of this book.

The scope of the study gives rise to another special methodological feature: I would like to call this approach “coupled scoping reviews.” The historical traumas that are the subject of the following chapters are so different from one another that it is necessary to present the respective scientific research for these traumas separately, according to the regional and ethnic constellations involved. Thus, the historical trauma experienced by Indigenous Americans is described separately from the Holocaust trauma sequelae, although research on the latter has influenced many concepts related to the former. Furthermore, in the case where gaps exist in the research, references will be made to other regional and ethnic trauma constellations. Consequently, each of the book’s chapters will represent a more or less self-contained scoping review, with the exception of the final chapter, which will attempt to create a summarizing bracket.

Empowerment Approach within Science Studies

The historical trauma concept, which will be detailed below, is imbued with a politically committed, emancipatory impetus. It is an integral component of anti-racist, anti-colonial, and pro-equality approaches. It is concerned with denouncing racist injustice, post-colonial dominance, the ongoing oppression of groups of people, and the lack of political pluralism as serious causes of suffering. The book will show that minorities of all kinds are particularly vulnerable to all kinds of suffering and pain because the majority societies oppose them in one form or another. There will be readers from the majority society who will therefore see this book as biased and doubt its scientific justification, because it assigns a share of the blame for the ethnic and political problems to the majority societies.

Accordingly, this book – along with the broader concept of political trauma – is part and parcel of engaged science. A pertinent debate exists as to whether science should always be impartial, as this would result in a loss of essential clarity and straightforwardness. An engaged approach could potentially cloud judgment in the hue and cry of the moment, with reason being excluded from the equation. This could lead to the dissemination of “fake news” instead. While the replication crisis in psychology and medicine is undoubtedly a significant challenge that has the potential to undermine the integrity of scientific research, it is unlikely that political commitment is the primary cause. Instead, the crisis is likely the result of inherent limitations in the scientific community, including a tendency toward ambition and time pressure.

Nevertheless, science studies have long justified the fundamental approach of engaged science as a place for reflecting on the work of researchers. In their studies on the new production of knowledge in contemporary societies, the science theorists Michael Gibbons, Helga Nowotny, and others assumed two modes of research.Footnote ⁴ Mode 1 science, also known as basic science, is committed to the centuries-old rules of knowledge production, whereby it has differentiated itself into many individual disciplines and sub-disciplines over the course of time. Mode 2 research, which is the subject of this book, is “context-driven,” problem-oriented, heterogeneous, transdisciplinary, anti-hierarchical, and global. Furthermore, it is cognizant of its social responsibility and engages in a comprehensive quality control process that is not limited to internal measures. Mode 2 research frequently occurs in collaborative partnerships between scientific and social actors. This will become evident in a moment when reference is made to the originator of the historical trauma concept, who is a paradigmatic example of a personal union between academic and social advocate.

The science studies orientation provides further good reasons why socially engaged research is fully justified in terms of epistemology. The sociologist of science Mario Bunge designated constructivism – which encompasses a significant portion of the methodological approach utilized by the social sciences – as an essential catalyst for the progressive accumulation of knowledge, via the fabrication of hypotheses and artifacts. To illustrate, consider the construct “conspiracy of silence” (regarding victims), which will be referenced in several subsequent chapters. It is assumed that this is an important operational factor of historical trauma effects. However, the possible indicators of this phenomenon are diverse and originate from various areas of the individual, collective, and societal psyche. The selected epistemological approach may also be considered pragmatic. This implies that the interaction between theoretical ideas and practical methods may result in the chosen solutions being at the expense of the (clearly defined and delimitable) ideas without the science losing any value. It is also relevant in the case of psychoanalytical explanations alongside psychological ones. The latter are known to originate from hermeneutics but often succeed in identifying ideas particularly succinctly. Mario Bunge concluded his remarks on Mode 2 by noting that positivism and rationalism, as exemplified by deductive quantitative research, can be relativized in this mode by the plurality of other methods of knowledge, such as hermeneutics.

These methodological and epistemological considerations were of significant importance to me at this juncture. I would now like to return to a more concrete and descriptive matter: What does the concept of historical trauma offer to those who wish to engage with it?

The New Concept of Historical Trauma

When the Indigenous social work scholar Maria Yellow Horse Brave Heart, who lives in North America, introduced the concept of historical trauma, she was concerned with the present-day effects of extreme historical injustice. In her case, this meant the fighting against and widespread annihilation of North American Indigenous peoples. While the distant effects of this are experienced individually, they are collective phenomena such as a persistent deep mourning and outrage over cultural losses. Moreover, they encompass the subsequent socio-economic injustices and vicious cycles of poverty, violence, addictive behavior, and general lack of opportunity.

In her writings, Brave Heart made reference to Holocaust impact research from the outset, particularly with regard to the knowledge available at the time on the transgenerational transmission of trauma impacts and the conspiracy of silence, originating, as previously mentioned, from psychoanalytic literature. However, she was also aware that other historical trauma constellations around the world were receiving increasing attention from clinicians and researchers around the millennium. These included the genocides against the Armenians (1915–1916), the Cambodian genocide (1975–1979), and the Rwandan genocide against the Tutsis (1994). In South Africa, following the end of apartheid in 1996, a process of reckoning with the past was initiated with the establishment of the Truth and Reconciliation Commission. Such commissions were subsequently established in numerous other countries to address historical atrocities, and their work has been extensively documented in numerous significant handbooks.Footnote ⁵

Brave Heart’s original historical trauma concept also facilitated the linkage of efforts for recovery and healing. In addition to focusing on the suffering experienced by her fellow natives, which was based on long-term effects, she was also committed to identifying actionable knowledge for improvement. This commitment was unflinching when defining the overarching notions of healing and growth, which remained controversial within the context of rational science at the time, as objectives. For the healing concept, this implied not only aiming rationally at the recovery of individual and collective states of suffering, but also aiming for a holistic concept of healing, which particularly included spirituality and ancestor worship. Consequently, the Western representation of humanity and the cosmos, which underpins the rational scientific discourse, has been supplanted by an alternative conceptual framework. However, Brave Heart’s approach to historical trauma research was distinct from other methodologies presented in this book. The Western image of humanity, which no longer necessitates a spiritual dimension or the role of ancestors, is a dominant paradigm in empirical research. As previously stated, the chosen broadly conceived science study orientation should allow for the consideration of perspectives that may initially appear foreign to and incompatible with Western views.

However, in order to ensure that a coupled scoping review with trauma contexts from six major world regions (North America, Africa, Europe, the Middle East, South Asia, and Southeast Asia) can be read coherently, this book is based on some basic definitional components of the historical trauma concept. These can be summarized as follows:

1. (1) A collective trauma was experienced in the past. This was typically manifested as enslavement, severe oppression, genocide, or war.

2. (2) There were intergenerational effects of trauma, with subsequent generations experiencing specific consequences.

3. (3) Further oppression, humiliation, racism, discrimination, and exclusion are still experienced in the present day. This often manifests as a “betrayal of institutions,” as described by Brave Heart.

4. (4) Social disadvantages and inequalities are still experienced by subsequent generations in the present day.

5. (5) The changes extend beyond the individual to encompass society as a whole. Persistent mistrust and communication barriers are evident.

6. (6) Remedies emerge, including a collective victim/affected narrative and the reference to one’s own identity as collective self-assurance.

The characteristics outlined above can be applied to a wide range of historical traumas occurring at different points in time: to illustrate, the approximately seven generations since the last battles of the North American Indians in the 1870s, the three generations since the Holocaust, the four to four and a half generations since the Stalinist and post-Stalinist repressions, and the half to one generation since the Rwandan genocide against the Tutsis. As some historians and journalists occasionally refer to historical traumas even in cases of earlier historical violence, these elements of the definition could be applied to such instances as well. In Germany, for instance, the lingering effects of the Thirty Years’ War (1618–1648), a conflict largely driven by religion, were already described in this way, but this immediately sparked professional debate.Footnote ⁶

I believe it is important to note that not every historical event can be defined as historical trauma. This is the case when characteristics (2) to (5) are absent or only weakly expressed. According to the definition provided, it would seem that the Second World War did not result in a historical trauma for the West Germans (the inhabitants of the Federal Republic of Germany). Germany was the primary aggressor in the 1930s, with Italy and Japan playing a role in supporting the aggression. However, the populations of these countries did not experience prolonged periods of oppression in the decades following 1945 after occupation by the victorious Allied forces. Although the military of the former aggressor countries like Germany was disarmed and assets were used to pay reparations to the Allies, there were generally no long-term occupations by the victorious powers. Albeit typically with some lag, health policy measures were implemented in the three countries to address health losses and offer (medical) treatment for the consequences of trauma. All three aggressor countries experienced economic growth, leading to increased prosperity for both former victims and former perpetrators. However, the same is not true for the smaller East Germany with the Soviets as the occupying power (see Chapter 5 on Stalinist and post-Stalinist repression).

From a terminological standpoint, it is also plausible to define the repercussions of catastrophic natural disasters (including lethal pandemics) as “historical traumas.” To illustrate, in 1556, one of the most destructive earthquakes in human history, with an estimated death toll surpassing 800,000 individuals, struck the Chinese province of Shaanxi and its neighboring regions. In 1970, a tropical cyclone in East Pakistan (now Bangladesh) resulted in the deaths of up to 500,000 people. The Spanish flu, an influenza virus pandemic, claimed the lives of 27 to 50 million people worldwide between 1918 and 1919, with the majority of victims in Asia and Africa.Footnote ⁷ The scale of destruction and suffering was so immense that there is no evidence that the direct survivors and their descendants exhibited characteristics (2) to (4) on our list. Similarly, the collective victim narrative mentioned under (6) does not usually exist for such natural disasters. It has been consistently noted by scholars in the field of history that the Spanish flu was one of the most lethal epidemics in human history.

Structure of the Book

The selection of the trauma constellations presented in this book is informed by a number of factors. As the table of contents indicates, the “typical constellations” are described in four chapters. This allows for a relatively straightforward alignment with the characteristics listed, although the respective structure of the chapters does not adhere to them in a slavish manner. The North American Indigenous peoples and HT research (from here on, the book will use the abbreviation HT for historical trauma) form the starting point (Chapter 2). The chapter on Holocaust survivors and their descendants follows, as their research provided many blueprints for HT research in general (Chapter 3). Geographically close to the HT context of the American Indigenous people, the HT of African Americans is dealt with next (Chapter 4). In this chapter, it will be apparent that the most frequently chosen term of reference is not HT but racial trauma, and the reasons for this are discussed in detail there. In the subsequent chapter, the historical context of the Soviet Union and its satellites is explored (Chapter 5). Originally, this chapter was supposed to have at least two sub-chapters (Soviet Russia on the one hand and all its satellite states on the other). However, the current state of research was not conducive to addressing this topic, given the considerable gaps in knowledge. So now, in 2025, a new aggressor (Russia) and a new victim of aggression (Ukraine) have been combined into one chapter for pragmatic reasons.

The four subsequent chapters present distinctive pathways or exceptional HT constellations, with each chapter varying one or more of the aforementioned HT characteristics. The relatively abbreviated Chapter 6 on Italian mafia victims addresses a collective trauma that began one hundred years ago but persists in the present due to the ongoing occurrence of mafia victimization. Although Rwandan Tutsi genocide survivors may no longer face overt discrimination and structural oppression in the current context, the danger does not appear to have permanently abated. Consequently, Chapter 7 examines the various research initiatives that potentially contributed to the transformation of collective trauma in 1994 into a historical phenomenon. The chapter on the Cambodian genocide (Chapter 8) focuses on a crucial aspect that is frequently overlooked: Despite the absence of direct discrimination against the victims, the subject of the genocide has been deliberately marginalized owing to political considerations. This phenomenon is even more pronounced in the context of the partition of India and Pakistan (Chapter 9). The victims of this displacement trauma are largely unacknowledged by their two countries, which has resulted in this trauma being almost exclusively an issue in the diaspora communities in distant countries. The concluding chapter (Chapter 10) presents a more detailed analysis of the compared contexts within the broader fields of historical studies and the humanities, as well as various conclusions from the perspective of science studies.

Who Is the Author Writing For?

After having presented the outline of the book, the methods, and the basic definition, it remains to be seen what the book is aiming to achieve. The author hopes that a book with results from the empirical sciences will be read at all, as it is well known that this type of science is published in journals for the researchers involved. Who among the authors in psychology and psychiatry still reads books? For those seeking a more comprehensive understanding of the field, the book offers a comprehensive overview of the subject matter, presenting a series of scoping reviews. When I was still a doctoral student in psychology, I found these books to be invaluable resources, providing a useful orientation in my field of research at the time. They made it possible to select the best focus of one’s research more effectively. In other words, they held a magnifying glass to one’s own research questions.

Historians and political scientists have their own reading habits. Historians rely on archival sources, while political scientists may utilize large-scale aggregated survey data. Both academic traditions tend to prioritize their own disciplines, with little engagement with other fields. Historians tend to focus on the exceptional, and statistical averages may not be necessary to support their arguments. This book will present various research findings, including those from qualitative social research. It is hoped that the perspectives presented in this book will facilitate interdisciplinary collaboration.

It is possible that researchers whose own work is cited within this book may be able to point to further connections and implications. Such expansions could prove to be invaluable in elucidating the topic of historical trauma. It is also likely that contradictions and content-related disputes might emerge. In contrast to the work of researchers and scholars of science, who are in a position to make critical assessments of the merits or demerits of specific research methodologies and outcomes, this book is not primarily intended to offer adversarial critiques of the research presented. Rather, it attempts to ascertain the productive aspects of all the published contributions to date. (If an idea did not appear to be viable to the author, it was excluded.) The objective of the entire undertaking is to achieve a multi-perspectival approach, with all its strengths and weaknesses.