After the Peace of Amiens was broken in 1803, Great Britain found herself at war with an old enemy (France) but also with a new competitor (Napoleon): the latter was the greatest military commander of his times, a man who was able to transform the French Army into the most lethal fighting machine of the early 19th century. The war experiences of 1793-1803 had not been very positive ones for the British Army; the latter was still recovering from the crushing defeats suffered during the American War of Independence and badly needed to be reformed in order to become more efficient and modern. At the turn of the new century, Great Britain was still the greatest colonial power of the world and could count on the most formidable navy of the world; on land, however, her army was too weak to confront the French one on almost equal terms. The British land forces did not have a great leader comparable to Napoleon and were still influenced by tactical models that had been outclassed by the events. During the Napoleonic Wars the British military apparatus did of its best to improve, especially thanks to the guidance of intelligent officers who belonged to a “new generation”. These innovative and capable men reformed the British Army, by improving its standards of service and by creating a new relationship (based on mutual trust) with the men under their command. Wellington was the greatest of these officers and one of the few European generals who had the personal capabilities to contrast Napoleon in an effective way: it was him who “forged” the new British Army, by fighting against the French in the Iberian Peninsula during 1808-1814. After learning from experience, the British soldiers were finally able to face Napoleon on the Belgian fields of Waterloo and thus they wrote the last page of a glorious military epic. Waterloo, however, was just the final result of a long process.