Massive hemorrhage remains the primary cause of preventable mortality on the battlefield. Lightweight, easy-to-use resuscitation products remain elusive in austere environments. The Canadian Armed Forces, along with Canadian Blood Services, is currently involved in the development of long-lasting and efficacious freeze-dried plasma as a potential tool to improve point-of-injury resuscitation. Canada has a long history of leading the development of freeze-dried blood products, and this history has not previously been explored in depth. In response to a blood shortage crisis during the Second World War, Canada started the first organized blood program, with a focus on creating freeze-dried blood products for the battlefield. This article discusses the foundation of Connaught Laboratories at the University of Toronto and its evolution as the production leader of freeze-dried blood products. Through an interesting cast of characters, including Dr. Charles Best, the story of how Canada became a leader in the research, development, and production of resuscitative medicine during the Second World War is explored. The story of Canada's leadership and ingenuity in early resuscitative medicine provides both an interesting context and an inspiration as tools to manage massive bleeds are rediscovered. LAY SUMMARY During the Second World War, Canada became a leader in the development and production of products used to treat shock, particularly shock caused by massive bleeds. Canada started the first blood service in response to the need for blood products overseas. This was done in the form of freeze-dried serum, which is made up of fluid-based proteins extracted from blood. Freeze-dried serum could be stored indefinitely and was lightweight, hardy, and easy to deliver both to the battlefield and to the patient. Freeze-dried serum could be provided to patients in shock as a result of losing a large volume of blood. Unfortunately, after the war, freeze-dried blood products fell out of favour over concerns about viral hepatitis. Recently, freeze-dried blood products have enjoyed a renaissance, and Canada is currently developing a new product to meet the challenges of remote resuscitation.