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migration,of people, geographical movements of individuals or groups for the purpose of permanently resettling.
Migrations have occurred throughout history and have played an important part in the peopling of all the areas of the earth. Primitive migrations were usually in search of food, but could also result from physical changes, such as the advance of the continental ice sheets, and invasion by other peoples. The most important migrations in European history were the Gothic invasions (3d–6th cent.; see GermansGermans,
great ethnic complex of ancient Europe, a basic stock in the composition of the modern peoples of Sweden, Norway, Denmark, Iceland, Germany, Austria, Switzerland, N Italy, the Netherlands, Belgium, Luxembourg, N and central France, Lowland Scotland, and England.
..... Click the link for more information. ), the Arab invasions (7th–8th cent.; see ArabsArabs,
name originally applied to the Semitic peoples of the Arabian Peninsula. It now refers to those persons whose primary language is Arabic. They constitute most of the population of Algeria, Bahrain, Egypt, Iraq, Jordan, Kuwait, Lebanon, Libya, Morocco, Oman, Qatar, Saudi
..... Click the link for more information. ), the westward migration of the Golden Horde of Jenghiz KhanJenghiz Khan
or Genghis Khan
, Mongolian Chinggis Khaan, 1167?–1227, Mongol conqueror, originally named Temujin. He succeeded his father, Yekusai, as chieftain of a Mongol tribe and then fought to become ruler of a Mongol confederacy.
..... Click the link for more information. (13th cent.), and the invasions of the Ottoman Turks (14th–16th cent.; see Ottoman EmpireOttoman Empire
, vast state founded in the late 13th cent. by Turkish tribes in Anatolia and ruled by the descendants of Osman I until its dissolution in 1918. Modern Turkey formed only part of the empire, but the terms "Turkey" and "Ottoman Empire" were often used
..... Click the link for more information. ; TurksTurks,
term applied in its wider meaning to the Turkic-speaking peoples of Turkey, Russia, Central Asia, Xinjiang in China (Chinese Turkistan), Azerbaijan and the Caucasus, Iran, and Afghanistan.
..... Click the link for more information. ).
From the 17th to the 20th cent. migration involved individuals and families rather than nations or mass groups. The basic motive was economic pressure, as areas of low population density attracted people from high-density areas where economic opportunity was low. The desire for religious and political freedom has also been important, and national policies have played a part. In the largest international migration in history, c.65 million people migrated from Europe to North America and South America between the 17th cent. and World War II, while another 17 million went to Africa and Australia.
Nearly 12 million people, most from Mexico or Asia, migrated to the United States in the 1970s and 80s. Within the United States, migration patterns have traditionally been from east to west. Migration from north to south since the 1960s has resulted in the ascendancy of the Sun BeltSun Belt
southern tier of the United States, focused on Florida, Texas, Arizona, and California, and extending as far north as Virginia. The term gained wide use in the 1970s, when the economic and political impact of the nation's overall shift in
..... Click the link for more information. , a region extending from Florida to S California. This trend has been supported by the southward migration of many blacks. Government regulation of migration became significant in the 20th cent. (see immigrationimmigration,
entrance of a person (an alien) into a new country for the purpose of establishing permanent residence. Motives for immigration, like those for migration generally, are often economic, although religious or political factors may be very important.
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Modern Migration Trends
Normal internal migration has been characterized by a population shift from rural to urban areas. In the United States, the portion of the population that lives in urban areas has risen steadily from 30% in 1910 to more than 70% in 1990; in Brazil, the percentage of urban dwellers has risen from 30% to 75% since 1940. Within urban areas, a large population shift from central cities to suburbs has occurred in the last half of the 20th cent. The development of totalitarianism and World War II resulted in a new pattern of forced mass migration within Europe. Over 30 million people were forcibly moved or scattered by the Nazis. In the postwar period c.10 million Germans and persons of German descent were forcibly expelled from Eastern Europe.
Other forced migrations since World War II have included the partitioning of India and Pakistan, which uprooted 18 million, and the establishment of the state of Israel, which created about one million refugees (see refugeerefugee,
one who leaves one's native land either because of expulsion or to escape persecution. The legal problem of accepting refugees is discussed under asylum; this article considers only mass dislocations and the organizations that help refugees.
..... Click the link for more information. ). After the fall of Saigon (now Ho Chi Minh City) at the end of the Vietnam WarVietnam War,
conflict in Southeast Asia, primarily fought in South Vietnam between government forces aided by the United States and guerrilla forces aided by North Vietnam. The war began soon after the Geneva Conference provisionally divided (1954) Vietnam at 17° N lat.
..... Click the link for more information. in 1975, more than 600,000 fled Vietnam in the face of political persecution; many fled by boat and became known as the "boat people." In South Africa, under the policies of apartheidapartheid
[Afrik.,=apartness], system of racial segregation peculiar to the Republic of South Africa, the legal basis of which was largely repealed in 1991–92. History
..... Click the link for more information. , blacks were forced to live in designated "homelands" from 1959 to 1994. The Soviet invasion of Afghanistan in 1979 led to the migration of millions of Afghans to neighboring Pakistan and Iran.
In the 1980s and 90s war and civil strife continued to force massive refugee migration in many parts of the world. In Somalia and Ethiopia, civil war combined with long-term drought have resulted in large migrations of peoples (often from rural to urban areas and to neighboring countries) in an attempt to avoid famine. Hundreds of thousands of Kurdish refugees (see KurdsKurds
, a non-Arab Middle Eastern minority population that inhabits the region known as Kurdistan, an extensive plateau and mountain area, c.74,000 sq mi (191,660 sq km), in SW Asia, including parts of E Turkey, NE Iraq, and NW Iran and smaller sections of NE Syria and
..... Click the link for more information. ) have migrated from Iraq to Turkey and Iran in the wake of the civil war that followed the Persian Gulf WarPersian Gulf Wars,
two conflicts involving Iraq and U.S.-led coalitions in the late 20th and early 21st cent.
The First Persian Gulf War, also known as the Gulf War, Jan.–Feb.
..... Click the link for more information. in 1991. The disintegration of Yugoslavia in the 1990s caused the dislocation of many peoples, especially Bosniaks, Croats, Serbs in areas other than Serbia, and Kosovars. In Rwanda and Burundi, millions of people, primarily Hutus, fled as ethnic civil war wrenched those nations in the mid-1990s; many of them fled to Zaïre (now Congo), where their presence aggravated civil and international strife.
See A. A. Brown and E. Neuberger, Internal Migration (1977); M. Greenwood, Migration and Economic Growth in the United States (1981); G. J. Lewis, Human Migration (1982); W. Weidlich and G. Haag, ed., Interregional Migration (1988); R. King, ed. Atlas of Human Migration (2007) and as author, People on the Move: An Atlas of Migration (2010); I Goldin et al., Exceptional People: How Migration Shaped Our World and Will Define Our Future (2011).
migrationthe movement of people from one country to another, involving an intention to reside in the country of destination. Emigration refers to the movement out of a country, immigration refers to the movement of people into a country. There is an internationally agreed definition of an immigrant as someone who, having lived outside the country for at least one year, declares an intention to live in the country for at least one year. An emigrant is defined in the opposite way Since World War II more people have emigrated from the UK than immigrated into it. In recent British history there have been three periods of marked immigration: Irish people 1800-61; Jewish people 1870-1911; and people from the New Commonwealth 1950-71. There have been a number of MORAL PANICS about immigration since 1945, focusing on the immigration of black people, and it is therefore important to distinguish between immigrants and black people; it is wrong to assume that an immigrant is black, and it is equally wrong to assume that a black person is an immigrant. See also LABOUR MIGRATION, ETHNIC GROUP, RACISM OR RACIALISM.
migrationTo move data or software from one location to another. Migration often means "copy" as much as it does "move." For example, "let's migrate our photos from the computer to the tablet" does not necessarily connote the photos are deleted from the computer after the transfer. Following are the various kinds of migration that take place in the computer world.
Moving data from one storage system to another for efficiency, backup or archiving. Also called "data migration." See HSM.
Moving application programs from one computer to another. See PC migration.
Moving data from a computer, tablet or smartphone to another device. See PC migration.
Moving a website or other Internet-based service from one ISP to another or from one server to another. See Internet domain name.
Moving an inhouse system to the cloud. See cloud computing.