Still was the son of a
Methodist minister and
physician. At an early age, Still decided to follow in his father's footsteps as a physician. After studying medicine and serving an apprenticeship under his father, he entered the
Civil War. He served as a hospital steward assigned to Company F of the Cass County Home Guard of the Missouri Cavalry (Union), but later stated in his autobiography that he served as a "de facto surgeon." At the time, the hospital stewards of the Army had many responsibilities, including maintaining hospital stores, furniture, and supplies for the sick. Since pharmacists were not provided for the hospitals, the hospital stewards also filled prescriptions, and when the medical officers were not present, they took care of the patients. In his autobiography, Still says he served in the Civil War in Company F of the
9th Kansas Cavalry. His military service record for the Missouri regiment says that his company was transferred to the 9th Kansas Infantry, not cavalry, but that the transfer was made "without proper authority." The judge advocate general then orders that these men not be given credit for this unauthorized service. The use of
Calomel, also known as mercury chloride, was one such medical practice Still took particular issue with. At the time, there were no standardized dosages for the drug so practitioners of
heroic medicine would often deliver dosages that were too large, resulting in
mercury poisoning. Still devoted the next thirty years of his life to studying the
human body and finding alternative ways to treat
disease; his methods involved meticulous anatomical dissection to discover its structure and, therefore, function. This involved exhuming corpses which, while controversial, was a widespread practice among many medical schools in the United States and abroad during that time. During this period, he completed a short course in medicine at the new College of Physicians and Surgeons in
Kansas City, Missouri, in 1870. Still adopted the ideas of
spiritualism sometime around 1867, and it "held a prominent and lasting place in his thinking." ==Kansas territorial and state legislator==