"Cannon-fodder" are the unfortunate mass of soldiery, doomed early in the battle because of inadequate equipment, training or leadership. Webster's Third International Dictionary traces it to the German Kanonenfutter. Then, Kanonenfutter is traced by German sources back to English. That's based on Shakespeare's image of "food for powder" in Henry IV, Part 1, IV: 2 ("Tut, tut! good enough to toss; food for powder, food for powder. They'll fill a pit as well as better"). See Adolf Bach, Geschichte der Deutschen Sprache, p. 315 (8th ed. 1965); Brockhaus' Konversationslexikon vol. 10, p. 98 (1894-96). Wikipedia's articles on cannon-fodder and Kanonenfutter suggest a circa-1814 French use of a similar term as the origin of the English "cannon-fodder."
Another notice for "fodder" today--Frederick I Barbarossa, German emperor in the mid-twelfth century, had the right to fodrum in the Italian territories he controlled, "a right to fodder for the royal army, and then to a payment in lieu of fodder." Geoffrey Barraclough, The Origins of Modern Germany, p. 180 (1984).