The death of Frederick Banting (insulin discoverer) on February 21, 1941 marked the end of the life of one of the most influential medical scientists of the twentieth century. Frederick Banting, a Canadian physician and researcher, gained worldwide recognition for the discovery of insulin and its vital role in the treatment of diabetes. The discovery of insulin in the 1920s transformed the lives of millions of diabetic patients around the world, and Banting, together with Charles Best, was awarded the Nobel Prize in Medicine in 1923. Throughout his life, Banting continued his scientific research and medical activities. During World War II, he served as a medical officer in the Canadian military. He died at the age of 49 in an air crash in Newfoundland while on a research mission. The accident also claimed the lives of two others. Banting's death shocked the global scientific and medical community, and he is remembered as a pioneer in diabetes treatment. In 1941, news of Banting's death received wide coverage in the media and scientific circles. Since then, the anniversary of his passing has served as a reminder of the crucial role of insulin in medical history and its impact on the lives of diabetic patients. This date was added to the Gregorian calendar in 1941 to commemorate Banting's significant scientific achievements and his lasting impact on the treatment of chronic diseases.