Middle Ages
Throughout the 14th century, French kings sought to expand their influence at the expense of the territorial holdings of the nobility. They ran into difficulties when attempting to confiscate the holdings of the English kings in southern France, leading to the Hundred Years' War, waged from 1337 to 1453. Early in the war the English under Edward III (r. 1327–77) and his son Edward, the Black Prince (d. 1376), won the battles of Crécy and Poitiers, captured the city of Calais, and won control of much of France. The resulting stresses almost caused the disintegration of the French kingdom during the early years of the war. In the early 15th century, France again came close to dissolving, but in the late 1420s the military successes of Joan of Arc (d. 1431) led to the victory of the French and the capture of the last English possessions in southern France in 1453. The price was high, as the population of France at the end of the Wars was likely half what it had been at the start of the conflict. Conversely, the Wars had a positive effect on English national identity, doing much to fuse the various local identities into a national English ideal. The conflict with France also helped create a national culture in England separate from French culture, which had previously been the dominant influence. The dominance of the English longbow began during early stages of the Hundred Years' War, and cannon appeared on the battlefield at Crécy in 1346.
France–United Kingdom relations
Several of the most famous Anglo-French battles took place during the Hundred Years' War: Crécy, Poitiers, Agincourt, Orléans, Patay, Formigny and Castillon. The English under King Henry VIII invaded and defeated France in 1544-46. Major sources of French pride stemmed from their leadership during the war. Bertrand du Guesclin was a brilliant tactician who forced the English out of the lands they had procured at the Treaty of Brétigny, a compromising treaty that most Frenchmen saw as a humiliation. Joan of Arc was another unifying figure who to this day represents a combination of religious fervour and French patriotism to all France. After her inspirational victory at Orléans and what many saw as Joan's martyrdom at the hands of Burgundians and Englishmen, Jean de Dunois eventually forced the English out of all of France except Calais, which was only lost in 1558. Apart from setting national identities, the Hundred Years' War was the root of the traditional rivalry and at times hatred between the two countries. During this era, the English lost their last territories in France, except Calais, which would remain in English hands for another 105 years, though the English monarchs continued to style themselves as Kings of France until 1800.