The war of 1809 between France and Habsburg Austria, culminating in the titanic battle of Wagram, has been described often as Napoleon’s last successful campaign. Napoleon said later that the manoeuvres and actions of the French army and their German allies in the opening two weeks of this conflict were among the most brilliant and skilful of his entire career. But matters might have gone very differently. A series of miscalculations, mistakes and poor communications, both prior to Austria’s declaration of war and in the early days of hostilities, might have resulted in a major setback, if not a disaster, for the French Emperor. That they did not is due in large part to the decisions and actions of Marshal Louis Davout, the so-called “Iron Marshall” This is the first English study of Marshal Davout's command and leadership in over fifty years. Little known outside of France, Louis Davout was one of the finest generals in Napoleon's army, as evidenced by his comprehensive defeat of the main Prussian force at Auerstadt in October 1806\. A hard, even harsh, disciplinarian, an utterly ruthless opponent on the field of battle, Davout was also a loving family man, meticulously concerned for the health and well-being of his troops, and able to command the loyalty of his divisional commanders for far longer than any of his contemporaries. In this new study, Martin Sullivan describes in detail the decision-making processes and actions of Marshal Davout, and from this analysis illustrates leadership concepts and theories which remain relevant to the world of today. Focusing upon the opening phase of the Wagram campaign, he examines in detail the decisions and actions of the participants, Davout, his opponent the Archduke Charles, and Napoleon himself. By this method the art of leadership may be seen exercised in the heat of an intense and deadly conflict.