The Hundred Years' War was a prolonged series of military conflicts between the English and French crowns and their allies, fought mainly during the period from 1337 to 1453. Despite its conventional name, the conflict did not last continuously for exactly one hundred years. It consisted of several phases of warfare separated by truces, negotiations and periods of relative peace.
The principal issues included competing claims to the French throne, disputes over territories held by English rulers in France, political and economic interests in regions such as Gascony and Flanders, and the wider struggle between the English and French monarchies for authority in western Europe. Major phases traditionally include the Edwardian War, the Caroline War, the Lancastrian War and the final French recovery under Charles VII.
Important battles included Crécy in 1346, Poitiers in 1356, Agincourt in 1415, and Castillon in 1453. The war involved more than England and France alone. Scottish, Burgundian, Breton, Castilian, Navarrese, Welsh and other forces became involved at different times. Its significance lies not only in military history but also in the development of monarchy, taxation, diplomacy, territorial government, military organisation and political identities in both kingdoms.
The immediate dynastic background arose from the extinction of the direct male line of the French Capetian dynasty in 1328. Edward III of England was the son of Isabella of France, daughter of Philip IV of France, and therefore possessed a claim through his mother. The French succession instead passed to Philip VI, a member of the Valois branch. French political principles and aristocratic precedent rejected Edward's claim, while Edward initially accepted Philip as king before relations deteriorated.
The English king also held territories in France as a feudal vassal of the French king, particularly Gascony in southwestern France. These possessions created a structural conflict because Edward was simultaneously a sovereign king in England and a subordinate vassal for his French lands. Disputes over jurisdiction, confiscations, inheritance and military support repeatedly strained relations. The French monarchy sought to reduce English territorial power in France, while the English monarchy wanted to preserve its possessions and influence.
Economic interests added another layer because England's wool trade was connected to the cloth producing regions of the Low Countries, while French and English interests intersected in trade and maritime affairs. The war therefore resulted from a combination of dynastic, territorial, feudal, economic and political factors rather than one isolated disagreement.
The first major phase began after Edward III formally asserted his claim to the French crown in 1340. English forces achieved notable victories under Edward III and his son Edward the Black Prince. At Crécy in 1346, the English army defeated a larger French force, with English longbowmen contributing significantly to the battle's outcome. The English subsequently captured Calais, which remained under English control for centuries and became an important strategic and commercial base.
In 1356, the Black Prince defeated and captured King John II of France at the Battle of Poitiers. The French monarchy faced severe financial and political difficulties, and the resulting Treaty of Brétigny in 1360 temporarily granted Edward III extensive territorial concessions while requiring him to renounce his claim to the French crown. The settlement did not create a durable peace.
Charles V of France reorganised French military and political resources and adopted a strategy that avoided unnecessary large battles while gradually recovering territory through sieges, raids and local campaigns. By the end of his reign, much of the English territorial expansion achieved under Edward III had been reversed. The war therefore moved through cycles of English success followed by French recovery rather than following a simple pattern of continuous English or French dominance.
The second major phase is associated with the reigns of Richard II, Henry IV, Henry V and Charles VI. Political instability in both kingdoms affected the conflict. Charles VI of France suffered recurring periods of severe illness, producing factional struggles among French nobles. In England, Henry IV had seized the throne from Richard II in 1399, and the Lancastrian dynasty subsequently sought to strengthen its legitimacy.
Henry V used military intervention in France both to pursue territorial and dynastic objectives and to consolidate his domestic authority. His invasion in 1415 produced the famous English victory at Agincourt. The Treaty of Troyes in 1420 recognised Henry V as heir to the French throne and arranged his marriage to Catherine of Valois, daughter of Charles VI. The treaty was contested because Charles VI's son, the future Charles VII, was excluded from succession under its terms.
Henry V died in 1422 before becoming king of France in practice, while Charles VI also died in the same year. Henry's infant son Henry VI inherited both crowns in the Lancastrian claim, but effective authority in France remained contested. The conflict then entered a new phase in which French recovery became increasingly successful.
Warfare during the Hundred Years' War involved far more than large open battles. Raiding, chevauchées, sieges, garrison warfare, naval operations, diplomacy and economic pressure were essential. English commanders frequently used mounted raids known as chevauchées to devastate agricultural areas, weaken local authority and force French rulers to respond. These operations could produce substantial destruction while avoiding the risks of major battles. Sieges were equally important because control of fortified towns and castles determined territorial authority.
Advances in gunpowder artillery gradually affected siege warfare, although medieval armies continued to rely extensively on traditional weapons and fortifications. English military success often depended on longbowmen, disciplined infantry and defensive positions, while French forces increasingly developed artillery and more centralised military organisation. The conflict also had serious effects on civilians. Farms, villages and towns could be destroyed or plundered, agricultural production disrupted and populations displaced. The war interacted with famine, epidemic disease and economic instability.
The Black Death, which reached Europe in the mid fourteenth century, caused enormous demographic losses during the conflict and affected taxation, labour markets and military recruitment. The war should therefore be understood as a social and economic crisis as well as a sequence of military engagements.
The final phase of the war was shaped strongly by Joan of Arc and the French recovery under Charles VII. In 1429 Joan participated in the lifting of the English siege of Orléans and subsequently accompanied French forces during a campaign that contributed to Charles's coronation at Reims. French recovery continued through military reforms, diplomacy and the gradual weakening of English territorial power.
The French monarchy developed more reliable taxation and permanent military forces, while the English crown faced financial and political difficulties. The death of important English commanders and the loss of Burgundian support also damaged the English position. The conflict ended gradually rather than through a single comprehensive peace treaty. French forces captured Normandy in the 1450s and defeated the remaining major English field army at Castillon in 1453.
England retained Calais, but nearly all other substantial English territories in France had been lost. The war therefore ended with French territorial consolidation and a significant strengthening of the French monarchy. England's defeat did not immediately produce the Wars of the Roses, but the costs and political consequences of the French campaigns contributed to tensions that later affected English politics.
The Hundred Years' War had profound consequences for state development and political identity. French kings expanded royal authority over territory that had previously been controlled by powerful nobles or foreign rulers. Regular taxation and military administration became increasingly important to the French monarchy. In England, parliamentary institutions became important in approving taxation required for prolonged warfare, although the relationship between monarchy and Parliament remained contested.
The war also encouraged the development of political concepts associated with English and French identity, although modern nationalism should not simply be projected backwards onto medieval society. Most people identified strongly with local communities, religious institutions, social estates and dynastic loyalties as well as broader kingdoms. The conflict nevertheless encouraged chroniclers and political writers to portray England and France as distinct communities with competing interests.
The languages of government and administration also developed differently, with English gradually returning to greater prominence in England after centuries of elite use of French and Latin. Military technology changed during the period, including increasingly effective gunpowder artillery, while recruitment and taxation became more organised. The conflict thus contributed to transformations that extended beyond the battlefield and helped shape the political structures of late medieval western Europe.
The Hundred Years' War should not be imagined as a continuous conflict lasting exactly one hundred years, nor as a simple national war fought only between two unified modern states. It was a series of interconnected dynastic, territorial and political struggles involving changing alliances and different phases. At various points, the English were highly successful and controlled large areas of France, while at other times French rulers recovered nearly all lost territories.
Burgundian politics, Scottish intervention, Castilian naval activity and internal French civil conflict all affected the course of the war. The conflict also illustrates the limitations of medieval kingship. Monarchs depended on nobles, military contractors, taxation and negotiated political support. Its final outcome was shaped by changes in administration and resources as much as by individual battles.
The war is historically significant because it transformed the territorial balance between England and France, strengthened the French monarchy, affected English political institutions and contributed to the development of military and fiscal systems. The conventional date of 1337 to 1453 is useful for historical organisation, but the war is better understood as a long sequence of connected conflicts with changing causes, participants and objectives rather than as one uninterrupted war.
