February 27th, 1915. On this day, The Valley of Fear by Arthur Conan Doyle is published in novel form.

Sherlock Holmes had been a popular character since he first appeared in the story "A Study in Scarlet," published in Beeton's Christmas Annual in 1887. The thin, highly strung detective with extraordinary deductive powers was modeled partly on Dr. Joseph Bell, a medical school teacher at the University of Edinburgh, where Holmes' creator studied.

Conan Doyle created Holmes while practicing medicine in London, where his shortage of patients left him ample free time to write. Starting in 1891, a series of Holmes stories appeared in The Strand magazine.

Holmes' success enabled Doyle to leave his medical practice in 1891 and devote himself to writing, but the author soon grew weary of his creation. In The Final Problem, he appeared to kill off both Holmes and his nemesis, Dr. Moriarty, only to resuscitate Holmes later due to popular demand.

In 1902, Doyle was knighted for his work with a field hospital in South Africa. In addition to dozens of Sherlock Holmes stories and several novels, Doyle wrote history, pursued whaling, and engaged in many adventures and athletic endeavors. After his son died in World War I, Doyle became a dedicated spiritualist. He died in 1930.