Infanterie Greift An (known as Infantry Attacks in English), is a classic book on military tactics written by German Field Marshal Erwin Rommel about his experiences in World War I. Rommel describes his Stoßtruppen (shock troops) tactics, which used speed, deception, and deep penetration into enemy territory to surprise and overwhelm. Throughout the book, Rommel reports assigning small numbers of men to approach enemy lines from the direction in which attack was expected. The men would yell, throw hand grenades and otherwise simulate the anticipated attack from concealment, while attack squads and larger bodies of men sneaked to the flanks and rears of the defenders to take them by surprise. These tactics often intimidated enemies into surrendering, thus avoiding unnecessary exertion, expe