The IISH is a unique institute, serving science and society on a global scale. At an international level, we generate and offer reliable information and insights about the (long-term) origins, effects and consequences of social inequality.

To promote this, we form an international hub for social historians worldwide. We offer and produce historical sources and data, facilitate socio-economic history research and collaborate internationally in ground breaking research projects.

Moreover, by preserving the heritage of often oppressed social movements, the Institute serves the quality of the world's memory. With our work we hope to contribute to a vibrant civil society.

iisg buiolding dawn



How to explain the ups and downs in social inequality from a global perspective? We try to answer this question by studying the different conditions under which workers  (from high to low) are remunerated. The working hypothesis is that shifts in labour relations, embedded in larger societal structures, can help us to understand changes in long term patterns of social inequality, both within and between world regions.


In order to answer these questions, the IISH works in close collaboration with  researchers in other continents to gather and analyse data about social and economic changes worldwide from 1500 onwards. The researchers study labour relations, individual life cycles, survival strategies, migrations, and collective actions, as well as time series of wages, prices, monetization, productivity, gender relations, life expectancies, and literacy.


The work- and labour relations perspective, is essential to find out how inequality comes about and is perpetuated, within and between societies. Through this research, the Institute aims to contribute to current social discussions about social inequality, economic growth, the environment, globalization, migration, and democracy.




The IISH collections comprise of material about social movements and people connected to those movements,  whose heritage is often not included in state archives, or in some countries it may even be under threat of being seized or destroyed by the central government. The IISH provides an option to deposit those endangered archives, so that they will remain part of society's collective memory. In this sense, the Institute fulfils an important societal role. Without the IISH, essential archival material would have been lost to society.


In more than 80 years, the Institute has built one of the largest socioeconomic historical collections in the world, with over 4,000 archives, 1 million books, 550,000 photos, 100,000 posters, more than 6,000,000 digital objects and datasets. In total, the IISH helds 50 kilometres of collections on its premises.


The IISH collections comprise archive, library and audio-visual material with a thematic emphasis on social and emancipatory movements. Between 2012 and 2017, the reading room received an average of 6,127 visits per year, which amounts to 24 visitors per day.