The Hundred Years' War transformed how European armies fought. The English longbow, the rise of professional infantry, and the early use of gunpowder weapons all challenged the dominance of mounted knights, reshaping battlefield tactics in ways that would echo for centuries. The conflict also highlighted a stark contrast between English and French strategies, with each side adapting to new threats in different ways.
Longbow's Impact on English Success
Longbow's Tactical Advantages
The English longbow was the defining weapon of the war's early and middle phases. With an effective range of up to 200 meters, it allowed archers to strike enemies well before they could close to melee range. English armies typically deployed longbowmen in huge numbers, often making up more than half the total force.
What made the longbow so devastating was the combination of rate of fire and penetrating power:
- A trained longbowman could loose 10–12 arrows per minute, creating a near-constant rain of projectiles on advancing troops.
- Bodkin-tipped arrows (narrow, hardened points designed for armor penetration) could punch through most armor at closer ranges, threatening even well-protected knights.
This meant that massed longbow fire could break up cavalry charges and shatter infantry formations before they ever reached English lines.
Longbow's Influence on Key Battles and Tactics
English victories at Crécy (1346) and Poitiers (1356) were built on the devastating effect of concentrated longbow fire.
- At Crécy, English longbowmen first shredded the Genoese crossbowmen the French had deployed as a screen, then tore into the French cavalry as it charged uphill. The result was a decisive English victory against a much larger force.
- At Poitiers, a smaller English army again defeated a larger French force, with longbowmen disrupting French formations and creating openings for English men-at-arms to exploit.
These repeated defeats forced the French to rethink their approach:
- The French began fielding more dismounted men-at-arms, reducing their reliance on cavalry charges that were so vulnerable to arrow fire.
- They also deployed crossbowmen to engage English archers. Crossbows had a slower rate of fire but could be used at comparable ranges and required less training.
Infantry's Rise vs Knight's Decline
Factors Contributing to Infantry's Increased Importance
The longbow was only part of the story. Across Europe, infantry was becoming more effective thanks to better tactics and formations.
- Dismounted men-at-arms, armed with polearms and swords, could anchor a defensive line that cavalry struggled to break through.
- Pikemen, wielding long spears, presented a wall of points that horses would not willingly charge into.
- Professional mercenary infantry, like the Genoese crossbowmen hired by France, offered flexibility and specialized skills that feudal levies could not match.
Together, these developments meant that well-organized foot soldiers could hold their ground against mounted knights, something that would have been unusual a century earlier.
Declining Role of Mounted Knights
The Battle of Agincourt (1415) became the most dramatic illustration of the mounted knight's vulnerability. The French cavalry advanced across a narrow, rain-soaked field and became bogged down in deep mud. English longbowmen cut them apart, and dismounted English men-at-arms finished the work at close quarters. The French suffered catastrophic losses.
Beyond the battlefield, economic pressures also drove the shift away from knights:
- Equipping and training a mounted knight was enormously expensive, requiring warhorses, full plate armor, and years of practice.
- Professional infantry, recruited from the lower classes and armed with pikes, bows, or later firearms, were far cheaper to field in large numbers.
Over the course of the war, European armies increasingly relied on professional standing forces built around infantry rather than feudal cavalry. The knight didn't vanish overnight, but the trend was unmistakable.
Gunpowder Weapons' Development and Use
Early Gunpowder Weapons and Their Limitations
Gunpowder weapons appeared on European battlefields during the 14th century and grew more common as the Hundred Years' War progressed. Their impact during this period was modest, but the trajectory was clear.
Cannons were used primarily in siege warfare:
- They were heavy, difficult to transport, and painfully slow to reload.
- Despite these drawbacks, they proved effective at battering down castle walls and fortifications during prolonged sieges, a task that previously required weeks of undermining or starving out defenders.
Handguns, such as the early arquebus, appeared in the war's later stages:
- These primitive firearms were slow to reload and inaccurate beyond short distances.
- However, groups of infantry firing in volleys could deliver punishing damage against tightly packed formations, and the shots could penetrate armor that arrows sometimes could not.
Impact on Fortress Design and Future Warfare
As cannons grew more powerful, fortress design had to adapt. Traditional tall, thin castle walls were vulnerable to cannon fire, so military engineers began building differently:
- Walls became thicker and lower to present a smaller target and better absorb impacts.
- Star forts emerged, featuring angled walls and projecting bastions that deflected cannonballs and eliminated blind spots for defenders.
- Earthworks were incorporated to absorb artillery shock more effectively than stone alone.
While gunpowder weapons played a supporting role during the Hundred Years' War itself, the technology improved rapidly afterward. Within a century, firearms and artillery would dominate European battlefields and render traditional castle defenses obsolete.
English vs French Military Strategies
English Strategies and Tactics
The English approach combined defensive battlefield tactics with aggressive raiding campaigns.
On the battlefield, English commanders consistently chose favorable ground and let the enemy come to them:
- They selected positions on hillsides, behind hedges, or in narrow passages that funneled attackers into the killing zone of their longbowmen.
- They reinforced positions with stakes driven into the ground and shallow trenches to slow cavalry charges.
Strategically, the English relied heavily on chevauchées, fast-moving raids through French territory:
- These raids burned farms, destroyed crops, slaughtered livestock, and sacked towns, aiming to cripple the French economy and tax base.
- Chevauchées also demoralized the French population and undermined confidence in the French crown's ability to protect its subjects.
The English generally fielded smaller, more mobile armies. Their reliance on longbowmen and light infantry meant they could move quickly, strike hard, and avoid the logistical burden of feeding a massive force deep in enemy territory.
French Strategies and Tactics
The French took a fundamentally different approach, shaped by their larger population, greater resources, and deep attachment to chivalric tradition.
- Early in the war, the French relied on massed cavalry charges led by armored knights. The nobility viewed mounted combat as the only honorable way to fight, and they were slow to abandon it even after repeated disasters.
- After the losses at Crécy, Poitiers, and Agincourt, the French gradually incorporated more infantry and gunpowder weapons into their armies. By the war's final decades, French forces looked very different from those that had charged at Crécy.
Strategically, the French focused on holding key cities and fortresses like Paris and Orléans, denying the English permanent footholds in the French heartland. They also used siege warfare and attrition, hoping to wear down English armies through supply shortages and disease rather than risking another pitched battle.
The French tended to field larger but less maneuverable forces, heavy with armored knights and men-at-arms. This gave them raw power in close combat but made them vulnerable to the English tactics of choosing favorable ground and forcing the French to attack on unfavorable terms.
Diplomatic Efforts and Alliances
Both sides worked to build alliances that could tip the balance:
- England allied with Flanders (a major economic partner due to the wool trade) and Brittany, gaining strategic footholds on the continent and additional military support.
- France cultivated the Auld Alliance with Scotland and sought support from Castile, aiming to force England to fight on multiple fronts.
These alliances had real consequences. The Scottish alliance, for example, forced England to keep troops stationed along its northern border, diverting resources from the French campaign. The Flemish alliance gave England financial support and a staging area for operations across the Channel.