Released in October 2014, the online encyclopedia is the result of an international collaborative project to make available a multi-perspective, public-access knowledge base on the First World War.

WWI Centenary Site - UK National Archives

Europeana 1914-1918 brings together resources from three major European projects each dealing with different types of First World War material. 

Brigham Young University WWI Document Archive

Online sources for European history

UK National Archives Education Exhibit