Abstract: In Australia, our history with nuclear matter and its processes has its origins in the early twentieth-century scientific adventurism of famed Antarctic explorer Douglas Mawson. As much as Mawson’s life has come to be defined by his forays into the ice, an examination of his personal and academic papers provides insight into how his relationship with radium was also of great importance, mirroring the shifting political and historical forces impacting upon the geologist. These are forces that he impacted in turn. Further to this, charting Mawson’s relationship with the radioactive from 1904 until his death in 1958 demonstrates the ways that Australia’s nuclear history entwines with scientific discovery, settler nationalistic ambition and colonialism.