The commemoration of disasters is a product of social, cultural, economic, and political forces in human society. Southern California's largely unheard-of St. Francis Dam Disaster of 1928 provides an excellent opportunity to study this complex process of commemoration, engaging memory within difference frames of reference. In particular, evaluating how and why this man-made dam disaster has been forgotten on a state and national level, but tenuously remembered within the flood-zone, allows for consideration of the diversity of commemorative processes in the construction of memory and heritage related to major catastrophes. This research synthesizes archival and survey data to better understand how the disaster and the dead have been commemorated throughout the 54-mile flood zone: spatially, through state monuments, community memorials, grave markers, and memorabilia, and conceptually, through poems, songs, and oral histories. Identifying what parts of the past are remembered, and how they are remembered and interpreted, provides understanding of how public memory develops. Further, being able to determine the factors that influence why certain things are remembered and memorialized, while other things are forgotten, can provide insight into not only the individual motivations and perceptions related to the creation of memory, but also to the larger issues of how a culture establishes both legends and traditions.