The English-language encyclopedia has been online since October 2014. It depicts World War I as the first global war in which numerous non-European countries as well as European countries were involved. The "1914-1918-online" project documents the increasingly international research on World War I and contributes to closing gaps in the research.

Contributions for the encyclopedia are written by experts from different countries and subjected to a two-stage review process by the editors and external experts. The editorial board and the scientific advisory board are composed of 90 renowned historians from 22 countries.

In addition to the Friedrich Meinecke Institute of History and the Center for Digital Systems, both of Freie Universität, the Bavarian State Library is the third main institution involved in the ongoing project. In addition, 30 partners in 13 countries support the project, including the German Historical Institute in London, Moscow, Paris, Rome, and Warsaw and the Orient Institute in Istanbul. The project is being funded with approximately one million euros by the German Research Foundation (DFG).