Thousands of medieval manuscripts were destroyed during the Second World War. Among all the material losses of the war, these were especially tragic, since medieval manuscripts, by their very nature, are handmade and uniquely irreplaceable. Yet fragments of these lost artifacts remain in the form of editions, photographs, and descriptions. As this short paper will discuss, I am currently working on gathering together these fragments, thanks to funding from the Netherlands Organisation for Scientific Research. The fragments will be used to digitally reconstruct the destroyed manuscript collections of four European nations and compiled into an online catalogue. Sections of the catalogue, where relevant, will be encoded in sustainable XML to protect these fragments against further loss. This catalogue will serve as a case study for exploring how digital technology, and the immaterial archival possibilities it entails, can help us think through the limits of the archive.