To the right you will see a page from a 1915 British tailoring journal explaining the newfangled "trench coat" to its subscribers:
"This coat in various forms is now being extensively advertised and freely sold by most of our leading military outfitters... Broadly speaking the coat is an over garment cut in the "sac" form and made very roomy to provide for ease... The coats are usually finished, as our diagram shows, in a double-breasted form, although some tailors cut them single-breasted with five holes and buttons down the front."
Click here to read about the fashion legacy of W.W. II: the t-shirt...