Rome’s western fall rode waves of moving peoples
From roughly 300 to 600 AD, historians mark a Migration Period when Goths, Vandals, Huns, and many others entered or crossed former Roman lands. Some date it tighter—from the Hunnic push about 375 to the Lombards in Italy in 568—while looser frames stretch toward 800.
Traditional narratives cast these movements as barbarian invasions that toppled the Western Empire and seeded post-Roman kingdoms. Groups ranged from small war bands of a few thousand to tribal coalitions over 100,000 strong. Modern estimates put the Gothic Danube crossing of 376 at roughly 90,000–200,000 people, and the surprise Rhine crossing of 406 by Vandals, Alans and Suebi at up to 200,000.
Other figures fill out the scale. The Ostrogoths under Theodoric numbered perhaps 100,000–200,000 when they entered Italy in 489, the Lombards around 150,000 in 568, and Anglo-Saxon settlers in Britain anywhere from 20,000 to 200,000. Added together, total movement into Roman territory may have run from about half a million to more than a million people. Frankish, Burgundian and Slavic numbers resist counting because those groups settled gradually rather than in one surge.
Movement was not simply imposed on Rome. In the fourth century the empire itself settled a large body of Goths as treaty allies in the Balkans and let Franks live south of the Rhine in Gaul. As central authority weakened, its army came to be dominated by men of barbarian origin, and historians still argue whether migration broke the West or a crumbling state drew migrants in. The eastern half adapted, partly steered the western breakup, and lasted until Constantinople fell to the Ottomans in 1453.
German scholars speak of Völkerwanderungen, first by Germanic peoples such as Goths, Vandals, Anglo-Saxons, Lombards, Jutes and Franks, some of whom were later pushed west by Huns, Avars, Slavs and Bulgars. Afterwards Vikings, Normans, Arabs, Turks and Mongols reshaped former Roman lands again, especially North Africa, Iberia and Anatolia.
Source: Migration Period
