In the history of Europe, the Middle Ages or medieval period lasted approximately from the 5th to late 15th centuries, comparable with the post-classical period of global history. The medieval period is the middle epoch of the three traditional divisions of Western history: classical antiquity, the medieval period, and the modern period. The medieval period is itself subdivided into the Early, High, and Late Middle Ages.

The Middle Ages began with the fall of the Western Roman Empire and transitioned into the Modern age during the Renaissance, the Reformation, the European wars of religion, and the Age of Discovery. Early Modernity is a single term adopted to describe this end-stage of the period, during which medieval Europe shades into the modern period.

Population decline, counterurbanisation, the collapse of centralised authority, invasions, and mass migrations of tribes had begun in late antiquity () and lasted into the Early Middle Ages (). The large-scale movements of the Migration Period, including various Germanic peoples, formed new kingdoms in what remained of the Western Roman Empire. In the 7th century, North Africa and the Middle East—once part of the Byzantine Empire—came under the rule of the Umayyad Caliphate, an Islamic empire, after conquest by Muhammad's successors. Although there were substantial changes in society and political structures, the break with classical antiquity was incomplete. The still-sizeable Byzantine Empire, Rome's direct continuation, survived in the Eastern Mediterranean and remained a major power. The empire's law code, the Corpus Juris Civilis or "Code of Justinian", was rediscovered in Northern Italy in the 11th century. In the West, most kingdoms incorporated the few extant Roman institutions. Monasteries were founded as campaigns to Christianise the remaining pagans across Europe continued. The Franks, under the Carolingian dynasty, briefly established the Carolingian Empire during the later 8th and early 9th centuries. It covered much of Western Europe but later succumbed to the pressures of internal civil wars combined with external invasions: Vikings from the north, Magyars from the east, and Saracens from the south.

During the High Middle Ages, which began after 1000, the population of Europe increased significantly as technological and agricultural innovations allowed trade to flourish and the Medieval Warm Period climate change allowed crop yields to increase. Manorialism, the organisation of peasants into villages that owed rent and labour services to the nobles, and feudalism, the political structure whereby knights and lower-status nobles owed military service to their overlords in return for the right to rent from lands and manors, were two of the ways society was organised in the High Middle Ages. This period also saw the collapse of the unified Christian church with the East–West Schism of 1054. The Crusades, first preached in 1095, were military attempts by Western European Christians to regain control of the Holy Land from Muslims. Kings became the heads of centralised nation-states, reducing crime and violence but making the ideal of a unified Christendom more distant. Intellectual life was marked by scholasticism, a philosophy that emphasised joining faith to reason, and by the founding of universities. The theology of Thomas Aquinas, the paintings of Giotto, the poetry of Dante and Chaucer, the travels of Marco Polo, and the Gothic architecture of cathedrals such as Chartres are among the outstanding achievements toward the end of this period and into the Late Middle Ages.

The Late Middle Ages was marked by difficulties and calamities, including famine, plague, and war, which significantly diminished the population of Europe; between 1347 and 1350, the Black Death killed about a third of Europeans. Controversy, heresy, and the Western Schism within the Catholic Church paralleled the interstate conflict, civil strife, and peasant revolts that occurred in the kingdoms. Cultural and technological developments transformed European society, concluding the Late Middle Ages and beginning the early modern period.

Terminology and periodisation The Middle Ages is one of the three major periods in the most enduring scheme for analysing European history: classical civilisation or antiquity, the Middle Ages and the modern period.Power Central Middle Ages p. 3 The "Middle Ages" first appears in Latin in 1469 as media tempestas or "middle season".Miglio "Curial Humanism" Interpretations of Renaissance Humanism p. 112 In early usage, there were many variants, including medium aevum, or "middle age", first recorded in 1604,Albrow Global Age p. 205 and media saecula, or "middle centuries", first recorded in 1625. The adjective "medieval" (or sometimes "mediaeval" or "mediæval"),"Mediaeval" Compact Edition of the Oxford English Dictionary meaning pertaining to the Middle Ages, derives from .Flexner (ed.) Random House Dictionary p. 1194

Medieval writers divided history into periods such as the "Six Ages" or the "Four Empires" and considered their time to be the last before the end of the world.Mommsen "Petrarch's Conception of the 'Dark Ages'" Speculum pp. 238 When referring to their own times, they spoke of them as being "modern".Singman Daily Life p. x In the 1330s, the Italian humanist and poet Petrarch referred to pre-Christian times as ('ancient') and to the Christian period as ('new').Knox "History of the Idea of the Renaissance" Petrarch regarded the post-Roman centuries as "dark" compared to the "light" of classical antiquity.Mommsen "Petrarch's Conception of the 'Dark Ages'" Speculum pp. 227–228 Leonardo Bruni was the first historian to use tripartite periodisation in his History of the Florentine People (1442), with a middle period "between the fall of the Roman Empire and the revival of city life sometime in late eleventh and twelfth centuries".Bruni History of the Florentine people pp. xvii–xviii Tripartite periodisation became standard after the 17th-century German historian Christoph Cellarius divided history into three periods: ancient, medieval, and modern.Murray "Should the Middle Ages Be Abolished?" Essays in Medieval Studies p. 4

The most commonly given starting point for the Middle Ages is around 500,"Middle Ages" Dictionary.com with the date of 476 first used by Bruni--mapping to the removal of the last (native) Roman emperor in the West from power and his replacement by a German chieftain. Later starting dates are sometimes used in the outer parts of Europe.1. 'The Byzantine Exception'-By 475 the Roman Empire had been split in two, with the Eastern Empire being ruled from Constantinople which does not 'fall' in the sense that the Western division of the Empire did.

2. The Dimension of Mediterannean Trade-In a famously controversial thesis, the medievalist Henri Pirenne claims that the Middle Ages as we understand them does not properly begin until the Ummayid conquest of the Visigoths (Spain) in 711 cements the Caliphate's dominance of Mediterranean sea routes. Though fiercely criticized, aspects of this view have more recently been redeemed by later scholarship.*

3. Scnadinavia-Also: For example, Scandinavia in Helle, Kouri, and Olesen (ed.) Cambridge History of Scandinavia Part 1 where the start date is 1000 (on page 6) or Russia in Martin Medieval Russia 980–1584

"Trade and the end of antiquity - Discussion Paper" (PDF). LSE Research Online. September 2024. For Europe as a whole, 1500 is often considered to be the end of the Middle Ages,See the titles of Watts Making of Polities Europe 1300–1500 or Epstein Economic History of Later Medieval Europe 1000–1500 or the end date used in Holmes (ed.) Oxford History of Medieval Europe but there is no universally agreed upon end date. Depending on the context, events such as the conquest of Constantinople by the Turks in 1453, Christopher Columbus's first voyage to the Americas in 1492, or the Reformation in 1517 are sometimes used. English historians often use the Battle of Bosworth Field in 1485 to mark the end of the period.See the title of Saul Companion to Medieval England 1066–1485 For Spain, dates commonly used are the death of King Ferdinand II in 1516, the death of Queen Isabella I of Castile in 1504, or the conquest of Granada in 1492.Kamen Spain 1469–1714 p. 29 1648, marking the end of the European wars of religion, might be considered an upper-bound that preserves the tripartite schema of the terminology (classical antiquity, the medieval, and the modern).Walter Benjamin. Origins of German Tragic Drama (1928). 76-77. The European Renaissance, the Reformation, and Early Modernity would, in that case, all refer to a transition between the Middle Ages and modernity in Western Europe instead of being counted as their own periods, similar to the way that the fall of the Western Roman Empire (occurring over a period of centuries) marks the beginning of the medieval period. By the end of the Thirty Years War, this transition has been accomplished in a geopolitical sense and the territory previously known as Christendom begins to be called Europe.

Historians from Romance-speaking countries tend to divide the Middle Ages into two parts: an earlier "High" and later "Low" period. English-speaking historians, following their German counterparts, generally subdivide the Middle Ages into three intervals: "Early", "High", and "Late". In the 19th century, the entire Middle Ages were often referred to as the "Dark Ages", but with the adoption of these subdivisions, use of this term was restricted to the Early Middle Ages, at least among historians.Mommsen "Petrarch's Conception of the 'Dark Ages'" Speculum p. 226

Later Roman Empire

The Roman Empire reached its greatest territorial extent during the 2nd century AD; the following two centuries witnessed the slow decline of Roman control over its outlying territories.Cunliffe Europe Between the Oceans pp. 391–393 Economic issues, including inflation, and external pressure on the frontiers combined to create the Crisis of the Third Century, with emperors coming to the throne only to be rapidly replaced by new usurpers.Collins Early Medieval Europe pp. 3–5 Military expenses increased steadily during the 3rd century, mainly in response to the war with the Sasanian Empire, which revived in the middle of the 3rd century. The army doubled in size, and cavalry and smaller units replaced the Roman legion as the main tactical unit.Brown World of Late Antiquity pp. 24–25 The need for revenue led to increased taxes and a decline in numbers of the curial, or landowning, class, and decreasing numbers of them willing to shoulder the burdens of holding office in their native towns.Heather Fall of the Roman Empire p. 111 More bureaucrats were needed in the central administration to deal with the needs of the army, which led to complaints from civilians that there were more tax-collectors in the empire than tax-payers.