The following are notable events in the Timeline of immunology:

• 1549 – The earliest account of inoculation of smallpox (variolation) occurs in Wan Quan's (1499–1582) Douzhen Xinfa (痘疹心法).^[1]
• 1718 – Smallpox inoculation in Ottoman Empire realized by West, and Lady Mary Wortley Montagu, recorded the positive effects of variolation.
• 1796 – First demonstration of smallpox vaccination (Edward Jenner)
• 1808 – 1813 - First experimental demonstration of the germ theory of disease by Agostino Bassi though he does not formally propose the theory until 1844
• 1837 – Description of the role of microbes in putrefaction and fermentation (Theodore Schwann)
• 1838 – Confirmation of the role of yeast in fermentation of sugar to alcohol (Charles Cagniard-Latour)
• 1850 – Demonstration of the contagious nature of puerperal fever (childbed fever) (Ignaz Semmelweis)
• 1857–1870 – Confirmation of the role of microbes in fermentation (Louis Pasteur)
• 1862 – Phagocytosis (Ernst Haeckel)
• 1867 – Aseptic practice in surgery using carbolic acid (Joseph Lister)
• 1876 – Demonstration that microbes can cause disease-anthrax (Robert Koch)
• 1877 – Mast cells (Paul Ehrlich)
• 1878 – Confirmation and popularization of the germ theory of disease (Louis Pasteur)
• 1880 – 81 Theory that bacterial virulence could be attenuated by culture in vitro and used as vaccines. Used to make chicken cholera and anthrax "vaccines" (Louis Pasteur)
• 1883 – 1905 – Cellular theory of immunity via phagocytosis by macrophages and microphages (polymorhonuclear leukocytes) (Elie Metchnikoff)
• 1885 – Introduction of concept of a "therapeutic vaccination". Report of a live "attenuated" vaccine for rabies (Louis Pasteur and Pierre Paul Émile Roux).
• 1888 – Identification of bacterial toxins (diphtheria bacillus) (Pierre Roux and Alexandre Yersin)
• 1888 – Bactericidal action of blood (George Nuttall)
• 1890 – Demonstration of antibody activity against diphtheria and tetanus toxins. Beginning of humoral theory of immunity. (Emil von Behring) and (Kitasato Shibasaburō)
• 1891 – Demonstration of cutaneous (delayed type) hypersensitivity (Robert Koch)
• 1893 – Use of live bacteria and bacterial lysates to treat tumors-"Coley's Toxins" (William B. Coley)
• 1894 – Bacteriolysis (Richard Pfeiffer)
• 1896 – An antibacterial, heat-labile serum component (complement) is described (Jules Bordet)
• 1900 – Antibody formation theory (Paul Ehrlich)
• 1901 – Blood groups (Karl Landsteiner)
• 1902 – Immediate hypersensitivity anaphylaxis (Paul Portier) and (Charles Richet)
• 1903 – Intermediate hypersensitivity, the "Arthus reaction" (Maurice Arthus)
• 1903 – Opsonization^[2]
• 1905 – "Serum sickness" allergy (Clemens von Pirquet and (Bela Schick)
• 1909 – Paul Ehrlich proposes "immune surveillance" hypothesis of tumor recognition and eradication
• 1911 – 2nd demonstration of filterable agent that caused tumors (Peyton Rous)
• 1917 – Hapten (Karl Landsteiner)
• 1921 – Cutaneous allergic reactions (Otto Prausnitz and Heinz Küstner)
• 1924 – Reticuloendothelial system
• 1938 – Antigen-Antibody binding hypothesis (John Marrack)
• 1940 – Identification of the Rh antigens (Karl Land

  The following are notable events in the Timeline of immunology:

  • 1549 – The earliest account of inoculation of smallpox (variolation) occurs in Wan Quan's (1499–1582) Douzhen Xinfa (痘疹心法).