In 1995-96, the Chicago Pediatric Society (CPS), one of the oldest pediatric societies in the USA, celebrated its first centennial; yet little was known about its founder and the first president. Standard historical sources stated that in 1895, one Dr. John C. Cook (1850-1908), met with friends at his house to discuss pediatric cases, the group later became the CPS. Based on my research I will present a biographic sketch of Dr. Cook and the methods of historiography. Dr. Cook was an influential physician working in several Chicago hospitals. He was the Chairman of the AMA's Section on Diseases of Children, and a pioneer in the crusade against contaminated milk. He started pure milk stations in the city's parks. Much of his writing has been lost but his papers on child development, GI disorders, pneumonia, adverse effects of child labor etc., are pediatric classics (e.g.,JAMA, 1903-1904; Illinois Medical Journal, 1903-1906). Dr. Cook fought passionately against child labor. The allure of the industrial revolution in the turn of the century Chicago spread its powerful web attracting children as young as eight years of age into the labor market. The immigrant families were particular targets. The schools were bad and the high school dropout rate was 95%. Dr. Cook noted these trends and wrote and spoke against child labor. Under the banner of the Physicians' Club of Chicago, a socially active group he founded, he organized public rallies, forums and debates on the topic of child labor. With stark examples, he described its adverse effects on children's health, growth, and development, and dispelled the notion that such labor was needed for economic growth. He tried to improve the standards of education in the schools such that children were attracted to the classrooms more than to the cotton mills. His work paid off---in July of 1903, revolutionary reforms were adopted in Illinois Child Labor Laws. However, I felt most humbled by Dr. Cook's anonymity from the cruelty of history's amnesia; a mere century later, this man, once a high-profile physician, was completely unknown---not even a portrait of him could be found. However, to my delight, I discovered the site of Dr. Cook's home in a cozy corner in Chicago's Hyde Park. This, 120-year-old, charming mansion has been wonderfully restored by its current owners, who also possess many of Dr. Cook's personal belongings and letters. Efforts are now underway to have the street renamed Dr. John C. Cook Avenue, and to have the birthplace of CPS designated an Historic landmark.