Studies of ionizing radiation effects through the archiving of data began with standardizing medical treatments in the early 1900s shortly after the discovery of X-rays. Once the breadth of the delayed effects of ionizing radiation was recognized, the need for long-term follow up became apparent. There are now many human archives of data from nuclear disasters and accidents, occupational exposures, and medical procedures. Planned animal irradiation experiments began around the time of the Cold War and included a variety of doses, fractions, dose rates, and types of ionizing radiation. The goal of most of these studies was to supplement information coming from human data through carefully planned experimental conditions and immediate and uninterrupted data collection. This review aims to highlight major archives and databases that have shaped the field of radiation biology and provide a broad range of the types of datasets currently available. By preserving all of these data and tissue sets, radiation biologists can combine databases and conduct large-scale analyses of detailed existing data and perform new assays with cutting edge scientific approaches.