The Middle East and North Africa used very different methods and equipment as was used in Europe, and there occurred a considerable amount of technological exchange and tactical adaptation between the different cultures. In Japan the Medieval warfare period is considered by many to have stretched into the eighteenth century. In Africa along the Sahel and Sudan, states like the Kingdom of Sennar and Fulani Empire employed Medieval tactics and weapons through the nineteenth century.
The infantry, including missile troops, would typically be employed at the outset of the battle to break open infantry formations while the cavalry attempted to defeat its opposing number. When one side gained superiority in cavalry (or had it at the outset of battle) it could attempt to exploit the loss of cohesion in the opposing infantry lines caused by the infantry conflict to hit the opposing infantry and attempt to rout it. This could often be difficult, and careful timing would be necessary for a direct cavalry assault, as an ordered infantry line would often be able to beat off the cavalry attacks. Pure infantry conflicts would be drawn-out affairs.
Cannons were introduced to the battlefield in the later medieval period. However, their very poor rate of fire (which often meant that only one shot was fired in the course of an entire battle) and their inaccuracy made them more of a psychological force multiplier than an effective anti-personnel weapon.
Later on in medieval warfare, once hand cannons were introduced, the rate of fire improved only slightly, but the cannons became far easier to aim, largely because they were smaller and much closer to their wielder. Their users could be easily protected, because the cannons were lighter and could be moved far more quickly. However, real field artillery did not become truly effective or commonly employed until well into the early modern period.
These fortifications evolved over the course of the Middle Ages, the most important form being the castle, a structure which had become synonymous with the Medieval era to many. The castle served as a protected place for the local elites. Inside a castle they were protected from bands of raiders and could send mounted warriors to drive the raiders from the area, or to disrupt the efforts of larger armies to supply themselves in the region by gaining local superiority over foraging parties that would be impossible against the whole enemy host.
Fortifications had a great many advantages. They provided refuge from armies too large to face in open battle. The ability of the heavy cavalry to dominate a battle on an open field was useless against fortifications. Building siege engines was a time-consuming process, and could seldom be effectively done without preparations before the campaign. Many sieges could take months, if not years, to weaken or demoralize the defenders sufficiently. Fortifications were an excellent means of ensuring that the elite could not be easily dislodged from their lands - as a French nobleman once commented on seeing enemy troops ravage his lands from the safety of his castle, "they can't take the land with them".
Advances in the prosecution of sieges encouraged the development of a variety of defensive counter-measures. In particular, medieval fortifications became progressively stronger — for example, the advent of the concentric castle from the period of the Crusades — and more dangerous to attackers — witness the increasing use of machicolations and murder-holes, as well the preparation of hot or incendiary substances. Arrow slits, concealed doors for sallies, and deep water wells were also integral to resisting siege at this time. Designers of castles paid particular attention to defending entrances, protecting gates with drawbridges, portcullises and barbicans. Wet animal skins were often draped over gates to retard fire. Moats and other water defenses, whether natural or augmented, were also vital to defenders.
In the European Middle Ages, virtually all large cities had city walls — Dubrovnik in Dalmatia is an impressive and well-preserved example — and more important cities had citadels, forts or castles. Great effort was expended to ensure a good water supply inside the city in case of siege. In some cases, long tunnels were constructed to carry water into the city. Complex systems of underground tunnels were used for storage and communications in medieval cities like Tábor in Bohemia. Against these would be matched the mining skills of teams of trained sappers, who were sometimes employed by besieging armies.
Until the invention of gunpowder-based weapons (and the resulting higher-velocity projectiles), the balance of power and logistics definitely favored the defender. With the invention of gunpowder, the traditional methods of defense became less and less effective against a determined siege.
As central governments grew in power, a return to the citizen armies of the classical period also began, as central levies of the peasantry began to be the central recruiting tool. England was one of the most centralized states in the Middle Ages, and the armies that fought the Hundred Years' War were mostly paid professionals. In theory, every Englishman had an obligation to serve for forty days. Forty days was not long enough for a campaign, especially one on the continent. Thus the scutage was introduced, whereby most Englishmen paid to escape their service and this money was used to create a permanent army. However, almost all high medieval armies in Europe were composed of a great deal of paid core troops, and there was a large mercenary market in Europe from at least the early twelfth century.
As the Middle Ages progressed in Italy, Italian cities began to rely mostly on mercenaries to do their fighting rather than the militias that had dominated the early and high medieval period in this region. These would be groups of career soldiers who would be paid a set rate. Mercenaries tended to be effective soldiers, especially in combination with standing forces, but in Italy they came to dominate the armies of the city states. This made them considerably less reliable than a standing army. Mercenary-on-mercenary warfare in Italy also led to relatively bloodless campaigns which relied as much on manoeuvre as on battles.
The knights were drawn to battle by feudal and social obligation, and also by the prospect of profit and advancement. Those who performed well were likely to increase their landholdings and advance in the social hierarchy. The prospect of significant income from pillage and ransoming prisoners was also important. For the mounted knight Medieval Warfare could be a relatively low risk affair. Nobles avoided killing each other for several reasons—for one thing, many were related to each other, had fought alongside one another, and they were all (more or less) members of the same elite culture; for another, a noble's ransom could be very high, and indeed some made a living by capturing and ransoming nobles in battle. Even peasants, who did not share the bonds of kinship and culture, would often avoid killing a nobleman, valuing the high ransom that a live capture could bring, as well as the valuable horse, armour and equipment that came with him. However, this is by no means a rule of medieval warfare. It was quite common, even at the height of "chivalric" warfare, for the knights to suffer heavy casualties during battles.
Plunder in itself was often the objective of a military campaign, to either pay mercenary forces, seize resources, reduce the fighting capacity of enemy forces, or as a calculated insult to the enemy ruler. Examples are the Viking attacks across Europe, or the highly destructive English chevauchées across northern France during the Hundred Years' War.
River and sea travel proved to be the easiest ways to transport supplies. During his invasion of the Levant, Richard I of England was forced to supply his army as it was marching through a barren desert. By marching his army along the shore, Richard was regularly resupplied by ships travelling along the coast. Likewise, as in Roman times, armies would frequently follow rivers while their supplies were being carried by barges. Supplying armies by mass land-transport would not become practical until the invention of rail transport and the internal combustion engine.
The baggage train provided an alternative supply method that was not dependent on access to a water-way. However, it was often a tactical liability. Supply chains forced armies to travel more slowly than a light skirmishing force and were typically centrally placed in the army, protected by the infantry and outriders. Attacks on an enemy's baggage when it was unprotected — as for instance the French attack on the English train at Agincourt, highlighted in the play Henry V—could cripple an army's ability to continue a campaign. This was particularly true in the case of sieges, when large amounts of supplies had to be provided for the besieging army. To refill its supply train, an army would forage extensively as well as resupply itself in cities or supply points - border castles were frequently stocked with supplies for this purpose.
Epidemics of diseases such as smallpox, cholera, typhoid, and dysentery often swept through medieval armies, especially when poorly supplied or sedentary. In a famous example, in 1347 the bubonic plague erupted in the besieging Mongol army outside the walls of Caffa, Crimea where the disease then spread throughout Europe as the Black Death.
For the inhabitants of a contested area, famine often followed protracted periods of warfare, because foraging armies ate any food stores they could find, reducing or depleting reserve stores. In addition, the overland routes taken by armies on the move could easily destroy a carefully planted field, preventing a crop the following season. Moreover, the death toll in war hit the farming labour pool particularly hard, making it even more difficult to recoup losses.
In the Mediterranean, naval warfare in the medieval period resembled that of the ancient period: fleets of galleys, often rowed by slaves, would attempt to ram each other, or come alongside for marines to fight on deck. This mode of naval warfare continued even into the early modern period, as, for example, at the Battle of Lepanto. Famous admirals included Andrea Doria, Hayreddin Barbarossa, and Don John of Austria.
However, galleys were fragile and difficult to use in the cold and turbulent North Sea and northern Atlantic, although they saw occasional use. Bulkier ships were developed which were primarily sail-driven, although the long lowboard Viking-style rowed longship saw use well into the fifteenth century. Ramming was unpractical with these sailing ships, but the main purpose of these warships remained the transportation of soldiers to fight on the decks of the opposing ship (as, for example, at the Battle of Svolder or the Battle of Sluys).
Warships resembled floating fortresses, with towers in the bows and at the stern (respectively, the forecastle and aftcastle). The large superstructure made these warships quite unstable, but the decisive defeats the more mobile but considerably lower boarded longships suffered at the hands of high-boarded cogs in the fifteenth century ended the issue of which ship type would dominate northern European warfare.
In the medieval period, it had proved difficult to mount cannons on board a warship, although some were placed in the fore- and aftcastles. Small hand-held anti-personnel cannons were used, but large cannons mounted on deck further compromised the stability of warships, and cannons at that time had a slow rate of fire and were inaccurate.
All this was about to change at the end of the medieval period. The insertion of an opening in the side of a ship, with a hinged cover, allowed the creation of a gundeck below the main deck. The weight of cannon distributed to lower decks of the ship increased its stability immensely, effectively providing ballast, and a row of cannon on a lower deck produced the broadside, where the weight of shot overcame the inherent inaccuracy of firing cannons from a ship at sea. An example is the Mary Rose, the flagship of King Henry VIII's fleet, which had around thirty cannon per side, all of which were capable of firing shot nine pounds or more. The Spanish took this concept and produced the galleon.
The English longbowman used a single-piece longbow to deliver arrows that could penetrate contemporary plate armour and mail. The longbow was a difficult weapon to master, requiring long years of use and consstant practice. A skilled longbowman could shoot over 20 arrows a minute, and 10 arrows a minute was used as the minimum standard. This rate of fire was far superior to competing weapons like the crossbow or early gunpowder weapons. The nearest competitor to the longbow was the much more expensive crossbow, used often by urban militias and mercenary forces. The crossbow had greater penetrating power, and did not require the extended years of training. However, it lacked the range of the longbow.
At the Crécy and Agincourt bowmen unleashed clouds of arrows into the ranks of knights. At Crécy, even 15,000 Genoese' crossbowmen could not dislodge them from their hill. At Agincourt, thousands of French knights were brought down by armour-piercing bodkin point arrows and horse-maiming broadheads. The longbowmen decimated an entire generation of the French nobility.
Since the longbow was difficult to deploy in a thrusting mobile offensive, it was best used in a defensive configuration. Bowmen were extended in thin lines and protected and screened by pits (as at the Battle of Bannockburn), staves or trenches. The terrain was usually chosen to put the archers at an advantage forcing their opponents into a bottleneck (at Agincourt) or a hard climb under fire (at Crécy). Sometimes the bowmen were deployed in a shallow "W", enabling them to trap and enfilade their foes.
The pike and the longbow put an end to the dominance of cavalry in European warfare, making the use of foot soldiers more important than they had been in recent years. Gunpowder eventually was to provoke even more significant changes. However, the heavy cavalry continued to be an important battlefield arm of European armies until the nineteenth century, when new and more accurate weapons made the mounted soldier too easy a target.
The most famous early Arab military commander was Khalid ibn al-Walid, also known as the Sword of Allah. In having the distinction of being undefeated in over a hundred battles against the numerically superior forces of the Roman Empire, Persian Empire, and their allies, Khalid is regarded as one of the finest military commanders in history. His greatest strategic achievements were his swift conquest of the Persian Empire and conquest of Roman Syria all within just three years from 633 to 636, while his greatest tactical achievements were his double envelopment manoeuvre against the larger Persian forces at the Battle of Walaja, and his decisive victories against the larger combined forces of the Persians, Romans, Greeks and Arab Christians at the Battle of Firaz, and the larger combined forces of Romans, Greeks, Ghassanids, Russians, Slavs, Franks, Georgians and Armenians at the Battle of Yarmouk.
Other famous Muslim military commanders included ‘Amr ibn al-‘As during the Muslim conquest of Egypt against the Roman Empire, Sa`d ibn Abi Waqqas at the Battle of al-Qādisiyyah against the Persian Empire, Tariq ibn-Ziyad during the Umayyad conquest of Hispania against the Visigoths, Ziyad ibn Salih at the Battle of Talas against the Chinese Tang Empire, and Saladin against the Crusaders.
The early Arab army mainly consisted of light infantry, with some light cavalry and a few camel cavalry. In contrast, the Roman army and Persian army at the time both had large numbers of heavy infantry (Roman legions and Persian daylami) and heavy cavalry (cataphracts and clibanarii) that were better equipped, heavily protected, and more experienced and disciplined. The Roman and Persian armies were also led by skilled generals such as Heraclius and Rostam Farrokhzād respectively. Despite being outnumbered by these superior Roman and Persian armies that were several times larger in almost every early battle, the Arabs were able to overcome the odds and defeat their enemies each time, mainly due to being led by tactical geniuses such as Khalid ibn al-Walid, ‘Amr ibn al-‘As, and Sa`d ibn Abi Waqqas, as well as the better mobility of light cavalry and light infantry units which allowed them to use better maneuvers, including various flanking maneuvers and pincer movements.
In particular, the double envelopment manoeuvre, which Khalid ibn al-Walid successfully used against the larger Persian forces at the Battle of Walaja, is regarded as one of the greatest tactical manoeuvres in history, and was only successfully used once before by Hannibal at the Battle of Cannae.
According to Steven Muhlberger of the ORB Encyclopedia, the "...vigor and prowess of the Arab armies" was due "... to the willingness of the great mass of the conquered population to make a deal with the Arab armies" and the "confidence of the Muslims" due to their religion and "esprit de corps.
Viking longships were easily manoeuvred, could navigate deep seas or shallow waters, and could carry warriors that could be quickly dispersed onto land due to the ability possessed by the longships to come straight up onto shore. The Viking style of warfare was fast and mobile, relying heavily on the element of surprise, and they tended to capture horses for mobility rather than carry them on their ships. The usual method was to approach a target stealthily, strike with surprise, then disperse and retire swiftly. The tactics used were difficult to stop, for the Vikings, like guerrilla style raiders elsewhere, deployed at a time and place of their own choosing. The fully armoured Viking raider would wear an iron helmet and a maille hauberk, and fight with a combination of axe, sword, shield, spear or great "Danish" two-handed axe, although the typical raider would be unarmoured, carrying only a shield, an axe, and possibly a spear.
Opponents of the Vikings were ill prepared to fight a force that struck at will, with no warning, then would disappear to attack other locations or retreat to their bases in what is now Sweden, Denmark, Norway and their atlantic colonies. As time went on, Viking raids became more sophisticated, with coordinated strikes involving multiple forces and large armies, as the "Great Heathen Army" that ravaged Anglo-Saxon England in the ninth century. In time the Vikings began to hold on to the areas they raided, first wintering and then consolidating footholds for expansion that were to change Europe forever.
With the growth of centralized authority in the Scandinavian region, Viking raids, always an expression of "private enterprise" ceased and the raids became pure voyages of conquest. In 1066, King Harald Hardråde of Norway invaded England, only to be defeated by Harold Godwinson, the son of one of Danish-Norwegian-English king Canute the Great's Earls, who in turn was defeated by William of Normandy, descendant of the Viking Rollo, who had accepted Normandy as a fief from the Frankish King. The three rulers all had their eyes on the English crown (Harald probably primarily on the overlord-ship of Northumbria), rather than being motivated by the lure of plunder.
At this point the Scandinavians had entered their medieval period, and the growth of centralized authority had formed the kingdoms of Denmark and Norway, and later the kingdom of Sweden. The Scandinavians started adapting more continental European ways, although they, and particularly the Norwegians, always had their own distinctive style in warfare with an emphasis on naval power from an early date - the "Viking" clinker-built warship was used effectively in war until the fourteenth century at least, and the larger Scandinavian warships in this style are all from the medieval period. However, the close trading and diplomatic links between Scandinavia and nearby catholic states ensured that the Scandinavians kept up to date with continental developments in warfare.
The Golden Horde would frequently clash with Hungarians, Lithuanians and Poles in the thirteenth century, with two large raids in the 1260s and 1280s respectively. In 1284 the Hungarians repelled the last major raid into Hungary, and in 1287 the Poles repelled a raid against them. The instability in the Golden Horde seems to have quieted the western front of the Horde. The Hungarians and Poles had responded to the mobile threat by extensive fortification-building, army reform in the form of better armoured cavalry, and refusing battle unless they could control the site of the battlefield to deny the Mongols local superiority. The Lithuanians relied on the their forested homelands for defense, and used their cavalry for raiding into Mongol-dominated Russia.
One notable victory was at Manzikert, where a conflict among the generals of the Byzantines gave the Turks the perfect opportunity to strike. They hit the cataphracts with arrows, and outmaneuvered them, then rode down their less mobile infantry with light cavalry that used scimitars. When gunpowder was introduced, the Ottoman Turks of the Ottoman Empire hired the mercenaries that used the gunpowder weapons and obtained their instruction for the Janissaries. Out of these Ottoman soldiers rose the Janissaries (yeni ceri; "new soldier"), from which they also recruited many of their unsung heroes, the heavy infantry. Along with the use of cavalry and early grenades, the Ottomans mounted an offensive in the early Renaissance period and attacked Europe, taking Constantinople with the help of their huge cannons that were bigger than their opponent's, notably Basilica, the giant that pounded the walls of Constantinople. Basilica was itself designed and cast for the Grand Turk by a Christian Hungarian named Urban. Despite its size, however, it was not very successful as an artillery piece due to its multiple-hour load rate.
Like many other nomadic peoples, the Turks featured a core of heavy cavalry from the upper classes. These evolved into the Sipahis (feudal landholders similar to western knights and Byzantine pronoiai) and Qapukulu (door slaves, taken from youth like Janissaries and trained to be royal servants and elite soldiers, mainly cataphracts).