Henry Knox, an American bookseller from Boston became the chief Artillery officer of the Continental Army and most notably the nation’s first United States Secretary of War. He was born to Scott-Irish immigrants William and Mary Campbell Knox in Boston on July 25, 1750. His father was a ship’s captain, engaged in the West Indies trade until his death in 1762. That same year Henry left school at the age of 12 and worked as a bookstore clerk to support his mother. Later he opened his own bookshop, the London Book Store, in Boston. Largely self-educated as an avid reader, he began to concentrate on military subjects, particularly Artillery.