"Human migration" denotes any movement by humans from one locality to another (migration), often over long distances or in large groups. Humans are known to have migrated extensively throughout history and prehistory.
Migration and population isolation is one of the four evolutionary forces (along with natural selection, genetic drift, and mutation). The study of the distribution of and change in allele (gene variations) frequencies under such influences is the discipline of Population genetics.
The movement of populations in modern times has continued under the form of both voluntary migration within one's region, country, or beyond, and involuntary migration (which includes slave trade, Trafficking in human beings and ethnic cleansing). The people who migrate are called migrants, or, more specifically, emigrants, immigrants or settlers, depending on historical setting, circumstance and perspective.
Different types of migration include:
- Daily human commuting can be compared to the diurnal migration of organisms in the oceans.
- Seasonal human migration is mainly related to agriculture.
- Permanent migration, for the purposes of permanent or long-term stays.
- Rural to Urban, more common in developing countries as industrialisation takes effect
- Urban to Rural, more common in developed countries due to a higher cost of urban living
Human migration has taken place at all times and in the greatest variety of circumstances. It has been tribal, national, class and individual. Its causes have been climatic, political, economic, religious, or mere love of adventure. Its causes and results are fundamental for the study of ethnology, of political and social history, and of political economy.
The pressures of human migrations, whether as outright conquest or by slow cultural infiltration and resettlement, have affected the grand epochs in history (e.g. the fall of the Western Roman Empire); under the form of colonization, migration has transformed the world (e.g. the prehistoric and historic settlements of Australia and the Americas). Population genetics studied in traditionally settled modern populations have opened a window into the historical patterns of migrations, a technique pioneered by Luigi Luca Cavalli-Sforza.
Forced migration (see population transfer) has been a means of social control under authoritarian regimes, yet under free initiative migration is a powerful factor in social adjustment (e.g. the growth of urban populations).
In December 2003 The Global Commission on International Migration (GCIM) was launched with the support of Kofi Annan and several countries, with an independent 19-member Commission, threefold mandate and a finite life-span, ending December 2005. Its report, based on regional consultation meetings with stakeholders and scientific reports from leading international migration experts, was published and presented to UN Secretary-General Kofi Annan on 5 October 2005. The 90-page Report, along with supporting evidence, is available on the GCIM website 
Evolution of the genus Homo took place in Africa (see Recent single-origin hypothesis). First Homo erectus migrated out of Africa across Eurasia, beginning about one million years ago, no doubt using some of the same available land routes north of the Himalayas that were later to become the Silk Road, and across the Strait of Gibraltar. Bruce Bower controversially suggested that Homo erectus may have built rafts and sailed oceans. 
The expansion of Homo erectus was followed by that of Homo sapiens. The matrilinear most recent common ancestor shared by all living human beings, dubbed Mitochondrial Eve, probably lived roughly 150-120 kya, the time of Homo sapiens idaltu, probably in the area of modern Ethiopia, Kenya or Tanzania. Around 100-80 kya, three main lines of Homo sapiens sapiens diverged, bearers of mitochondrial haplogroup L1 (mtDNA) / A (Y-DNA) colonizing Southern Africa (the ancestors of the Khoisan (Capoid) peoples), bearers of haplogroup L2 (mtDNA) / B (Y-DNA) settling Central and West Africa (the ancestors of Niger-Congo and Nilo-Saharan speaking peoples and of the Mbuti pygmies), while the bearers of haplogroup L3 remained in East Africa. Some 70 kya, a part of the L3 bearers migrated into the Near East, spreading east to southern Asia and Australasia some 60 kya, northwestwards into Europe and eastwards into Central Asia some 40 kya, and further east to the Americas from ca. 30 kya.
Migrations to the New World
There are two main models for the history of the first settlement of the Americas. One school of thought believes in a "short chronology," believing that the first movement into the New World occurred no earlier than 14,000 – 16,000 years ago. On the other hand, the "long chronology" camp posits that people entered the hemisphere at a much earlier date, theorizing the possibility of migration 20,000 years ago or earlier.
Agriculture is believed to have first been practiced some 10,000 years ago in the Fertile Crescent (see Jericho). From there it propagated as a "wave" across Europe, a view supported by Archaeogenetics, reaching northern Europe some 5,000 years ago.
The islands of the Pacific were the last region on Earth to be populated by humans, as recently as 15 to 12 millennia ago.
With the art of open-sea navigation involving the most confident and courageous use of the available technologies of boat-building, combined with the most sophisticated understanding of currents and prevailing winds, the Polynesians, starting with the Lapita culture, have proven to be the most successful in the art of navigation, if the permanent spread of culture is taken into account, for the Norse adventurers in the North Atlantic and the Arab traders in the Indian Ocean did not create permanent settlements. The Lapita people, who got their name from the archaeological site in Lapita, New Caledonia, where their characteristic pottery was first discovered, came from Austronesia, probably New Guinea. Their navigation skills took them to the Solomon Islands, around 1600 BC, and later to Fiji and Tonga. By the beginning of the 1st millennium BC, most of Polynesia was a loose web of thriving cultures who settled on the islands' coasts and lived off the sea. By 500 BC Micronesia was completely colonized; the last region of Polynesia to be reached was New Zealand in around AD 1000.
Polynesian migration patterns also have been studied by linguistic analysis, and recently by analyzing characteristic genetic alleles of today's inhabitants. Both methods resulted in supporting the original archaeological findings.
The Bantu first originated around the Benue-Cross rivers area in southeastern Nigeria and spread over Africa to the Zambia area. Sometime in the second millennium BC, perhaps triggered by the drying of the Sahara and pressure from the migration of people from the Sahara into the region, they were forced to expand into the rainforests of central Africa (phase I). In the 1st millennium BC, they began a more rapid second phase of expansion beyond the forests into southern and eastern Africa, and again in the 1st millennium AD as new agricultural techniques and plants were developed in Zambia, probably imported from South East Asia via Austronesian-speaking Madagascar (phase III). By about AD 1000 it had reached modern day Zimbabwe and South Africa. In Zimbabwe a major southern hemisphere empire was established, with its capital at Great Zimbabwe. By the 14th or 15th century, the Empire had surpassed its resources and had collapsed.
The Indo-European migration had variously been dated to the end of the Neolithic (Marija Gimbutas: Corded ware, Yamna, Kurgan), the early Neolithic (Colin Renfrew: Starčevo-Körös, Linearbandkeramic) and the late Palaeolithic (Marcel Otte, Paleolithic Continuity Theory).
The speakers of the Proto-Indo-European language are usually believed to have originated to the North of the Black Sea (today Eastern Ukraine and Southern Russia), and from there they gradually migrated into, and spread their language by cultural diffusion to, Anatolia, Europe, and Central Asia Iran and South Asia starting from around the end of the Neolithic period (see Kurgan hypothesis). Other theories, such as that of Colin Renfrew, posit their development much earlier, in Anatolia, and claim that Indo-European languages and culture spread as a result of the agricultural revolution in the early Neolithic.
Relatively little is known about the inhabitants of pre-Indo-European "Old Europe". They are believed to have been hunter-gathers. The Basque language remains from that era, as do the indigenous languages of the Caucasus. The Sami are genetically distinct among the peoples of Europe, but the Sami languages, as part of the Finno-Ugric languages, spread into Europe about the same time as the Indo-European languages. However, since that period speakers of other Finno-Ugric languages such as the Finns and the Estonians have had more contact with other Europeans, thus today sharing more genes with them than the Sami.
The earliest migrations we can reconstruct from historical sources are those of the 2nd millennium BC. It is speculated that the Proto-Indo-Iranians began their expansion from ca. 2000 BC, the Indo-Aryan migration hypothesis suggests that they reached Assyria in the west and the Punjab in the east by ca. 1500 BC. In the Late Bronze Age, the Aegean and Anatolia were overrun by moving populations, summarized as the "Sea Peoples", leading to the collapse of the Hittite Empire and ushering in the Iron Age.
Early Iron Age
The Dorian invasion of Greece led to the Greek Dark Ages. Very Little is known about the period of the 12th to 9th centuries BC, but there were significant population movements throughout Anatolia and the Iranian plateau. Iranian peoples invaded the territory of modern Iran in this period, taking over the Elamite Empire. The Urartians were displaced by Armenians, and the Cimmerians and the Mushki migrated from the Caucasus into Anatolia. A Thraco-Cimmerian connection links these movements to the Proto-Celtic world of central Europe, leading to the introduction of Iron to Europe and the Celtic expansion to western Europe and the British Isles around 500 BC.
The great migrations
Western historians refer to the period of migrations that separated Antiquity from the Middle Ages in Europe as the Great Migrations or as the Migrations Period. This period is further divided into two phases.
The first phase, from 300 to 500 AD, saw the movement of Germanic and other tribes and ended with the settlement of these peoples in the areas of the former Western Roman Empire, essentially causing its demise. (See also: Ostrogoths, Visigoths, Burgundians, Suebi, Alamanni Marcomanni).
The second phase, between 500 and 900 AD, saw Slavic, Turkic and other tribes on the move, re-settling in Eastern Europe and gradually making it predominantly Slavic. Moreover, more Germanic tribes migrated within Europe during this period, including the Lombards (to Italy), and the Angles, Saxons, and Jutes (to the British Isles). See also: Avars, Bulgars, Huns, Arabs, Vikings, Varangians. The last phase of the migrations saw the coming of the Hungarians to the Pannonian plain.
German historians of the 19th century referred to these Germanic migrations as the Völkerwanderung, the migrations of the peoples.
The European migration period is connected with the simultaneous Turkic expansion which at first displaced other peoples towards the west, and by High Medieval times, the Seljuk Turks themselves reached the Mediterranean.
Medieval and Early Modern Europe
The medieval period, although often presented as a time of limited human mobility and slow social change in the history of Europe, in fact saw widespread movement of peoples. The Vikings from Scandinavia raided all over Europe from 8th century and settled in many places, including Normandy, the north of England, Scotland and Ireland (most of whose urban centres were founded by the Vikings). The Normans later conquered the Saxon Kingdom of England, most of Ireland, southern Italy and Sicily -although the migration associated with these conquests was relatively limited - the Normans in most cases forming only a small ruling class. Iberia was invaded by Muslim Arabs, Berbers and Moors in the eighth century, founding new Kingdoms such as al Andalus and bringing with them a wave of settlers from North Africa.
In the other direction, European Christian armies conquered Palestine for a time during the Crusades 11th-13th centuries, founding three Christian kingdoms and settling them with Christian Knights and their families. This permanent migration was relatively small however and was one of the reasons why the Crusaders eventually lost the their hold on the Holy Lands.
In the 14th century, German military colonists settled the Baltic region, becoming a ruling elite. At the end of the Middle Ages, the Roma arrived in Europe (to Iberia and the Balkans) from the Middle East, originating from the Indus river.
Internal European migration stepped up in the Early Modern Period. In this period, major migration within Europe included the recruiting by monarchs of landless labourers to settle depopulated or uncultivated regions and a series of forced migration caused by religious persecution. Notable examples of this phenomenon include mass migration of Protestants from the Spanish Netherlands to the Dutch Republic after the 1580s, the expelling of Jews and Moriscos from Spain in the 1590s and the expulsion of the Huguenots from France in the 1680s. Since the 14th century, the Serbs started leaving the areas of their medieval Kingdom and Empire that was overrun by the Ottoman Turks and migrated to the north, to the lands of today's Vojvodina (northern Serbia), which was ruled by the Kingdom of Hungary at that time. The Habsburg monarchs of Austria encouraged them to settle on their frontier with the Turks and provide military service by granting them free land and religious toleration. The two greatest migrations took place in 1690 and 1737. Other instances of labour recruitments include the Plantations of Ireland - the settling of Ireland with Protestant English colonists in the period 1560-1690 and the recruitment of Germans by Catherine the Great of Russia to settle the Volga region in the 18th century.
European Colonialism from the 16th to the early 20th centuries led to an imposition of a European colonies in many regions of the world, particularly in the Americas, South Asia, Sub-Saharan Africa and Australia, where European languages remain either prevalent or in frequent use as administrative languages. Major human migration before the 18th century was largely state directed. For instance, Spanish emigration to the New World was limited to settlers from Castile who were intended to acts as soldiers or administrators. Mass immigration was not encouraged due to a labour shortage in Europe (of which Spain was the worst affected by a depopulation of its core territories in the 17th century). Europeans also tended to die of tropical diseases in the New World in this period and for this reason, England, France and Spain preferred using slaves to free labour in their American possessions. This changed in the 18th century due to population increases in Europe. Spanish restrictions on emigration to Latin America were revoked and the English colonies in North America saw a major influx of settlers attracted by cheap or free land, economic opportunity and religious toleration. By 1800, European emigration had transformed the demographic character of the American continent. Their influence elsewhere was less pronounced as in South Asia and Africa, European settlement in this period was limited to thin layer of administrators, traders and soldiers.
While the pace of migration had accelerated since the 18th century already (including the involuntary slave trade), it would increase further in the 19th century. Manning distinguishes three major types of migration: labour migration, refugee migrations and lastly: urbanisation. Millions of agricultural workers left the countryside and moved to the cities causing unprecedented levels of urbanisation. This phenomenon began in Britain in the late 18th century and spread around the world and continues to this day in many areas.
Industrialisation encouraged migration wherever it appeared. The increasingly global economy globalised the labour market. Atlantic slave trade diminished sharply after 1820, which gave rise to self-bound contract labour migration from Europe and Asia to plantations. Also overpopulation, open agricultural frontiers and rising industrial centres attracked voluntary, encouraged and sometimes coerced migration. Moreover, migration was significantly eased by improved transportation techniques.
Between 1846 and 1940 mass migrations occurred world wide. The size and speed of transnational migratory movements were unprecedented. Some 55 millions of migrants moved from Europe to America, and an additional 2,5 million moved from Asia to America. Of this transatlantic migrations, 65% went to the United States. Other major receiving countries were Argentina, Canada, Brazil and Cuba. (see also Immigration to the United States, Italian diaspora, Irish diaspora etc.)
During this same period similar large numbers of people migrated over large distances within Asia. Southeastern Asia received 50 million migrants, mainly from India and south China. North Asia, that be Manchuria, Siberia, Central Asia and Japan together, received another 50 million. A movement that started in the 1890's with migrants from China, Russia and Korea, and was especially large due to coerced migration from the Soviet Union and Japan in the 1930s. Less is known about exact numbers of the migrations from and within Africa in this period, but Africa experienced a small nett immigration between 1850 and 1950, from a variety of originins.
Transnational labour migration reached a peak of three million migrants per year in the early twentieth century. Italy, Norway, Ireland and the Quongdong region of China were regions with especially high emigration rates during these years. This large migration flows influenced the process of nation state formation in many ways. Immigration restrictions have been developed, as well as diaspora cultures and myths that reflect the importance of migration to the foundation of certain nations, like the American melting pot. The transnational labour migration fell to a lower level from 1930s to the 1960s and then rebounded.
The twentieth century experienced also an increase in migratory flows caused by war and politics. Muslims moved from the Balkan to Turkey, while Christians moved the other way, during the collapse of the Ottoman Empire. 400.000 Jews moved to Palestine in the early twentieth century. The Russian Revolution of 1917 caused some 3 million Russians, Poles and Germans to migrate out of the Soviet Union. World War II and decolonisation also caused migrations, see below.
Patrick Manning, Migration in World History (2005) p 132-162.
Adam McKeown, 'Global migration, 1846-1940' in: Journal of Global History (june 2004).
World War II
See World War II evacuation and expulsion for World War II forced migrations.
The Jewish diaspora across Europe, the Mediterranean and the Middle East formed from voluntary migrations, enslavement, threats of enslavement and pogroms. After the Nazis brought the Holocaust upon Jewish people in the 1940s, there was increased migration to the British Mandate of Palestine, which became the modern day state of Israel as a result of the 1947 UN Partition Plan.
Provisions of the Potsdam Agreement from 1945 signed by victorious Western Allies and the Soviet Union led to one of the largest European migrations, and definitely the largest in the 20th century. It involved the migration and resettlement of close to or over 20 million people. The largest affected group were 16.5 million Germans expelled from Eastern Europe westwards. The second largest group were Poles, millions of whom were expelled westwards from eastern Kresy region and resettled in the so-called Recovered Territories (see Allies decide Polish border in the article on the Oder-Neisse line). Hundreds of thousands of Ukrainians and some Bielorussians were in the meantime expelled eastwards, from Poland to the Soviet Union. Finally, many of the several hundred thousands Jews remaining in the Eastern Europe after the Holocaust migrated outside Europe to Israel.
- See also: Minorities in Poland after the War
The nowadays' most affected destinies are the USA, Russian Federation, UK, South Europe like Greece, Spain, Portugal, France and Italy; Australia, Luxembourg, Switzerland, Canada, Sweden, Norway and South Africa.
Migrations and climate cycles
The modern field of climate history suggests that the successive waves of Eurasian nomadic movement throughout history have had their origins in climatic cycles, which have expanded or contracted pastureland in Central Asia, especially Mongolia and the Altai. People were displaced from their home ground by other tribes trying to find land that could be grazed by essential flocks, each group pushing the next further to the south and west, into the highlands of Anatolia, the plains of Hungary, into Mesopotamia or southwards, into the rich pastures of China.
Toward an understanding of migration
Types of migrations
- The cyclic movement which involves commuting, a seasonal movement, and nomadism.
- The periodic movement which consists of migrant labor, military services, and pastoral farming Transhumance.
- The migratory movement that moves from the eastern part of the United States to the western part. It also moves from China to southeast Asia, from Europe to North America, and from South America to the middle part of the Americas.
- Internal migration
Ravenstein's 'laws of migration'
Certain laws of social science have been proposed to describe human migration. The following was a standard list after Ravenstein's proposals during the time frame of 1834 to 1913. The laws are as follows:
- Most migrants only go a short distance at one time.
- Long distance migrations are for those who come from large cities.
- Most migration is from rural areas to urban areas.
- Most international migrants consist of young males between the ages of 20 and 45.
- Most migrations proceed in step-by-step processes.
- Each migration flow produces at least one counterflow.
- Females remain more migratory than the males within their country.
- Migration increases in volume as industries develop and transportation improves.
- The economy is a major factor in migration.
Other migration models
- Zipf's Inverse distance law (1946)
- Gravity model and the Friction of distance
- Buffer Theory
- Stouffer's Theory of intervening opportunities (1940)
- Lee's Push-pull theory (1966)
- Bauder's Regulation of labor markets (2006)
Causes of migrations
Causes of migrations have modified over hundreds of years. Some cases are constant, some of them do not carry the same importance as years ago (for example: in 18th and 19th centuries labor migration did not have the same character like today).
In general we can divide factors causing migrations into two groups of factors: Push and pull factors. In general:
- Push Factors are economic, political, cultural, and environmentally based.
- Pull Factors are economic, political, cultural, and environmentally based.
- Barriers/Obstacles which is an example of Nigeria in the 1970s and 1980s.
Some certain factors are both push and pull like education, industry etc.
On the macro level, the causes of migration can be distilled into two main categories: security dimension of migration (natural disasters, conflicts, threats to individual safety, poor political prospects) and economic dimension of migration (poor economic situation, poor situation of national market). [AIV document]
Effects of migration
Migration like any other process shapes many fields of life, having both advantages and disadvantages. Effects of migrations are:
- changes in distribution of populationn
- mixing of different cultures and races (what often leads to negative social behaviors – tensions in society between majorities and minorities, followed often by local struggles and racism and racial discrimination. Also criminality growth can be caused.
- demographic consequences: since migration is selective of particular age groups, migrants are mostly young and in productive age. It can cause a demographic crisis – population ageing, what in turn can be followed by economic problems (shrinking group of economically active population has to finance extending group of inactive population).
- economic results, which are of the greatest importance for the development of the countries.
Migration in the European Union
The wages in the European Union are generally higher than the rest of Europe. That's why a lot of people from Eastern Europe want to migrate to the EU. But it's getting more and more difficult to migrate into the EU. The rules to migrate into the EU are very strict. Although some Eastern European countries are recently added to the EU. Those people can migrate easily to other EU countries.
Short distance migration
A new kind of migration is developing along the Dutch–Belgian and Dutch–German border. People migrate only a few kilometers across the border. They physically live abroad but their entire social life takes place inside the Netherlands. This kind of migration is very elastic. The main reason for migration is the attractive financial climate across the border. In Germany house prices are much lower. In Belgium the fiscal climate is very interesting. This also causes some social problems. The Dutch aren't likely to integrate. Most of them send their children to schools in the Netherlands. In Belgium there's the advantage of speaking the same language. As a result of the increasing demand for houses in some borderlands, the prices of houses are rising. The local community is afraid to move away because of the higher prices. Some municipalities indicated to think of ways to protect their region against short distance migrants.