Across the twentieth century, millions of people died in war and disaster, leaving their families to make sense of sudden loss and navigate newfound grief. In these circumstance, bereaved families were often denied access to bodies and choice over burial rights, all while dealing with an increased amount of death-based bureaucracy. In turn, this meant that the domestic memorials that they created took on additional meaning because of a lack of agency elsewhere. Drawing on a nuanced reading of a very wide range of sources - from ephemera and administrative museum paperwork to private records and modern family interviews - this book explores family reactions to such mass death events in early twentieth-century Britain to show how families were able to push against state-imposed memorial narratives and create and personalize objects to enable themselves to mourn. Although the ways that these families were bereaved each took place in different circumstances, the ways that families grieved were recognizable to one another: they drew on common memorial practices, augmented to take on special meaning after sudden death. This memorial material provided a vehicle for families to navigate their loss, but also to communicate the memory of the dead both externally, through donation to museums, and linearly, through ancestral lines. The result is a unique, comparative, and domestic perspective on mourning at the turn of the century that makes important contributions to the growing field of death studies, and will be of interest to those working on World War I, interwar Britain, the history of work the social history of the family, and the history of memorialization.