Using research methods well-known to family history investigators, it is possible to discover a remarkable amount of biographical information not merely on the officers, but also about the ratings who sailed — and died — with Sir John Franklin and Captain Francis Crozier on the 1845 Northwest Passage expedition. The findings from this research, mostly carried out at local and national archives in and around London, greatly enhances the understanding of that disaster, filling in gaps and answering questions raised by recent archaeological and forensic discoveries. This is the hitherto ignored social background to the last voyage of HMS Erebus and HMS Terror.