Summary: The sciences of vaccinology and of immunology were created just two centuries ago by Jenner's studies of prevention of smallpox by inoculation with cowpox virus. Tins rudimentary beginning was expanded greatly by the giants of late 19th and early 10th centuries, bio-medical sciences. The period from 1930 to 1950 was a transitional era with the introduction of chick embryos and minced tissues for propagating viruses and rickettsiae in vitro for vaccines. Modern era vaccinology began about i950 as a continuum of notable advances made during the 1940s and World War II. Present vaccinology is based largely on breakthroughs in cell culture, bacterial polysaccharide chemistry, molecular biology, and immunology By invitation, the author, who is a microbe hunter in fact, was asked to chronicle his six decades of pioneering achievements in basic and applied virology, bacteriology, immunology, molecular biology, epidemiology, and cancer, with special reference to the pioneering creation of most of the present day vaccines. Knowledge of the past may guide the present and future. This chronicle will have achieved its legacy if it helps others to understand the why and how of the past that may help to create the substance of the future.