Harrie Irving Hancock (1866?–1922) was an American chemist and writer, mainly remembered as an author of children's literature and juveniles in the late 19th and early 20th centuries, and as having written a fictional depiction of a German invasion of the United States.
Hancock was born in Massachusetts on January 16, 1868. His parents were William Henry and Laura (Oakes) Hancock. Hancock married Nellie Stein on December 21, 1887. They had two daughters, apparently adopted: Vivian Morris Hancock and Doris Hancock.
A prolific author who liked to work at night, Hancock wrote for the New York Journal, the New York World, and Leslie's Weekly. Much of his writing was the kind of "Boy's books" initiated by the famous Stratemeyer Syndicate, based on the assumption (which proved hugely successful) that "boys want the thrill of feeling 'grown-up'" and that they like books which give them that feeling to come in series where the same heroes appear again and again. However, the bulk of Hancock's works in that genre appear to have been handled by publishers other than Stratemeyer. (A comprehensive list of his publications does not yet exist, the list appearing on this page being far from complete).
For some time it was considered that, unlike other writers, he invariably used his own name, in the form "H. Irving Hancock". However, Edward T. LeBlanc and J. Randolph Cox, who researched the period's "dime novels", concluded that a series of books attributed to "Douglas Wells" were in fact written by Hancock.
The same researchers recount that Hancock "had been a journalist for the Boston Globe from 1885 to 1890, served as a war correspondent in Cuba and the Philippines during the Spanish–American War. He produced more than 50 serials for Norman Munro's juvenile magazine Golden Hours between 1889 and 1901.