It is commonly known that the First World War led to a flood of war memorials in the late 1910s and early 1920s. Before permanent memorials were constructed, ephemeral monuments and temporary commemorative arrangements such as (flower) shrines and wooden or plaster structures were erected in public spaces. Engelen and Sterckx concentrate on these very first public and material acts of remembrance. In formerly occupied territories, such as Belgium and Northern France, the need to express grief as well as gratitude – which had been suppressed by the occupation regime for over four years – exploded as soon as the armistice was signed. Ideas for monuments surfaced instantly on the national and local levels. Not all of these intentions materialised, and many did so only after a long time because the financial, logistic and administrative structures required to build permanent monuments were often missing. As a consequence, this determination to commemorate resulted in temporary ephemeral memorials. Through the contextualising and analysis of several early examples, the authors demonstrate the agency of civilians in these mostly grassroots initiatives and show that the design of these memorials meandered between existing (national, religious, artistic) traditions and spontaneous ad hoc creativity. Through the ephemeral nature of the memorials, the (literal) fragility of commemoration as well as the importance of the momentum for these practices is laid bare. The moment of their creation is indeed of crucial importance.