The Institute, founded in 1950, consists of a section for religious history and a section for general history, working together on a joint research programme. It employs over three dozen researchers working in historical disciplines. In cooperation with the Johannes Gutenberg University Mainz, the IEG runs a Research Training Group (Graduiertenkolleg) funded by the German Research Foundation. A comprehensive fellowship and exchange programme for PhDs and Postdocs as well as for Senior Researchers underscores the Institute’s commitment to promoting research at all levels. The IEG operates a library with specialist collections in the fields of the history of European Christianity and of general European history. Since 2012 the IEG has been part of the Leibniz Association.
The IEG conducts research into the historical foundations of Europe, their transformations and crises as well as conflicts and processes of communication and reconciliation. The central theme of the present research agenda at the IEG is »Negotiating Difference in Modern Europe«. In three research groups scholars analyse the various forms of establishing, overcoming and enabling differences, i.e. the regulation and limitation – but also the production and maintenance – of otherness and inequality within Europe and in its relations with the wider world. The cross-sectional project »EGO | European History Online« (www.ieg-ego.eu) covers five hundred years of European history across national, disciplinary and methodological boundaries.
Research results are published in the institute's own series "Veröffentlichungen des Instituts für Europäische Geschichte Mainz" (Publications of the Institute of European History in Mainz). The online services provided, such as digitalized versions of maps of Europe, European peace treaties and source editions of early modern controversial literature, are in heavy demand and make IEG internationally visible.