Deportation is the expulsion of a person or group of people from a place or country. The term expulsion is often used as a synonym for deportation, through expulsion is more often used in the context of international law, while deportation is more used in national (municipal) law. 
Definitions of deportation apply equally to nationals and foreigners. Nonetheless, in the common usage the expulsion of foreign nationals is usually called deportation, whereas the expulsion of nationals is called extradition, banishment, exile, or penal transportation. For example, in the United States:
"Strictly speaking, transportation, extradition, and deportation, although each has the effect of removing a person from the country, are different things, and have different purposes. Transportation is by way of punishment of one convicted of an offense against the laws of the country. Extradition is the surrender to another country of one accused of an offense against its laws, there to be tried, and, if found guilty, punished. Deportation is the removal of an alien out of the country, simply because his presence is deemed inconsistent with the public welfare and without any punishment being imposed or contemplated either under the laws of the country out of which he is sent or of those of the country to which he is taken."
Expulsion is an act by a public authority to remove a person or persons against his or her will from the territory of that state. A successful expulsion of a person by a country is called a deportation.
According to the European Court of Human Rights, collective expulsion is any measure compelling non-nationals, as a group, to leave a country, except where such a measure is taken on the basis of a reasonable and objective examination of the particular case of each individual non-national of the group. Mass expulsion may also occur when members of an ethnic group are sent out of a state regardless of nationality. Collective expulsion, or expulsion en masse, is prohibited by several instruments of international law.
Deportations widely occurred in ancient history.
In Achaemenid Empire
|Deported people||Deported to||Deporter|
|6,000 Egyptians (including the king Amyrtaeus and many artisans)||Susa||Cambyses II|
|Northwest African Barcaean captives||A village in Bactria||Darius I|
|Peonians of Thrace||Asia Minor|
|Milesians||Ampé on the Tigris|
|Carians and Sitacemians||Babylonia|
|Sidonian prisoners of war||Susa and Babylon||Artaxerxes III|
|Jews who supported the Sidonian revolt||Hyrcania||Artaxerxes III|
In Arsacid Empire
Unlike in the Achaemenid and Sassanian periods, records of deportation are rare during the Arsacid Parthian period. One notable example was the deportaion of the Mards in Charax, near Rhages (Ray) by Phraates I. The 10,000 Roman prisonors of war after the Battle of Carrhae appear to have been deported to Alexandria Margiana (Merv) near the eastern border in 53 BC, who are said to married to local people. It is hypothesized that some of them founded the Chinese city of Li-Jien after becoming soldiers for the Hsiung-nu, but this is doubted. 
In Sassanid Empire
Deportation was widely used by the Sasanians, especially during the wars with the Romans.
During Shapur I's reign, the Romans (including Valerian) who were defeated at the Battle of Edessa were deported to Persis. Other destinations were Parthia, Khuzestan, and Asorestan. There were cities which were founded and were populated by Romans prisoners of war, including Shadh-Shapur (Dayr Mikhraq) in Meshan, Bishapur in Persis, Wuzurg-Shapur ('Uqbara; Marw-Ḥābūr), and Gundeshapur. Agricultural land were also given to the deportees. These deportations initiated the spread Christianity in the Sassanian empire. In Rēw-Ardashīr (Rishahr; Yarānshahr), Persis, there was a church for the Romans and another one for Carmanians.  In the mid-3rd century, Greek-speaking deportees from north-western Syria were settled in Kashkar, Mesopotamia.
After the Arab incursion into Persia during Shapur II's reign, he scattered the defeated Arab tribes by deporting them to other regions. Some where deported to Bahrain and Kirman, possibly to both populate these unattractive regions (due to their climate) and bringing the tribes under control. 
In 395 AD, 18,000 Roman populations of Sophene, Armenia, Mesopotamia, Syria, and Cappadocia were captured and deported by the " Huns ". the prisoners were freed by the Persians as they reached Persia, and were settled in Slōk (Wēh Ardashīr) and Kōkbā (Kōkhē). The author of the text Liber Calipharum has praised the king Yazdegerd I (399-420) for his treatment of the deportees, who also allowed some to return. 
Major deportations occurred during the campaigns of Khosrau I from the Roman cities of Sura, Beroea, Antioch, Apamea, Callinicum, and Batnai in Osrhoene, to Wēh-Antiyōk-Khosrow (also known as Rūmagān; in Arabic: al-Rūmiyya). The city was founded near Ctesiphon especially for them, and Khosrow reportedly "did everything in his power to make the residents want to stay".  The number of the deportees is recorded to be 292,000 in another source.
Individual or mass forcible transfers, as well as deportations of protected persons from occupied territory to the territory of the Occupying Power or to that of any other country, occupied or not, are prohibited, regardless of their motive.... The Occupying Power shall not deport or transfer parts of its own civilian population into the territory it occupies.
All countries reserve the right to deport persons without right of abode, even those who are longtime residents and/or possess permanent residency. In general, foreigners who have committed serious crimes, entered the country illegally, overstayed and/or broken the conditions of their visa, or otherwise lost their legal status to remain in the country may be administratively removed or deported.  In some cases, even citizens can be deported; Saudi Arabia and the UAE for example.  Some western countries also have the ability to deport citizens, if they have another nationality or if they acquire citizenship through fraud.
In many cases, deportation is done by the government's executive apparatus, and as such is often subject to a simpler legal process (or none), with reduced or no right to trial, legal representation or appeal due to the subject's lack of citizenship. For example, in the 1930s, during the Great Depression, more stringent enforcement of immigration laws were ordered by the executive branch of the U.S. government, which led to the expulsion of up to 2 million Mexican nationals from the United States.  In 1954, the executive branch of the U.S. government implemented Operation Wetback, a program created in response to public hysteria about immigration and immigrants from Mexico.  Operation Wetback led to the deportation of nearly 1.3 million Mexicans from the United States.   Between 2009 and 2016, about 3.2 million people were deported from the United States.  Since 1997 U.S. mass deportations of non-citizens particularly convicted felons have risen steadily with the passing into law by the U.S. Congress of the 1996 Illegal Immigration Reform and Responsibility Act (IIRRA) which brought sweeping changes to the threshold for deportation of convicted felons  that have been criticized by some as having human rights abuses . Since this time, the former U.S. Immigration and Naturalization Services (INS) has been transformed into Immigration and Customs Enforcement (ICE) and has renamed deportation as "expedited removal". The ICE website publishes removal statistics annually on its website. According to recent numbers ICE removed a total of 240,255 aliens in FY 2016, a two percent increase over FY 2015, but a 24 percent decrease from FY 2014 .
Already in natural law of the 18th century, philosophers agreed that expulsion of a nation from the territory that it historically inhabits is not allowable.  In the late 20th century, the United Nations drafted a code related to crimes against humanity; Article 18 of the Draft Code of Crimes Against the Peace and Security of Mankind declares "large scale" arbitrary or forcible deportation to be a crime against humanity.
Deportation often requires a specific process that must be validated by a court or senior government official. It should not be confused with administrative removal, which is the process of a country denying entry to individuals at a port of entry and expelling them.
Deportation can also happen within a state, when (for example) an individual or a group of people is forcibly resettled to a different part of the country. If ethnic groups are affected by this, it may also be referred to as population transfer. The rationale is often that these groups might assist the enemy in war or insurrection. For example, the American state of Georgia deported 400 female mill workers during the Civil War on the suspicion they were Northern sympathizers.
During World War II, Joseph Stalin (see Population transfer in the Soviet Union) ordered the deportation of Volga Germans, Chechens, Crimean Tatars, Ukrainians and others to areas away from the front, including central and western Soviet Union. Some historians have estimated the number of deaths from the deportation to be as high as 1 in 3 among some populations. On February 26, 2004 the European Parliament characterized deportations of the Chechens as an act of genocide. 
The Soviet Union also used deportation, as well as instituting the Russian language as the only working language and other such tactics, to achieve Russification of its occupied territories (such as the Baltic nations and Bessarabia). In this way, it removed the historical ethnic populations and repopulated the areas with Russian nationals. The deported people were sent to remote, scarcely populated areas or to GULAG labour camps. It has been estimated that, in their entirety, internal forced migrations affected some 6 million people.  Of these, some 1 to 1.5 million perished.
After World War II approximately 50,000 Hungarians were deported from South Slovakia by Czechoslovak authorities to the Czech borderlands in order to alter the ethnic composition of the region. Between 110,000 and 120,000 Japanese and Japanese Americans on the West Coast, as well as about 3,000 Italian American and about 11,500 German American families, were forcibly resettled from the coasts to internment camps in interior areas of the United States of America by President Franklin Roosevelt.
In the late 19th and early 20th century, deportation of union members and labor leaders was not uncommon in the United States during strikes or labor disputes. For an example, see the Bisbee Deportation. 
Deporting individuals to a colony is a special case that is neither completely internal nor external. Such deportation has occurred in history. For example, after 1717, Britain deported around 40,000 :5 religious objectors and criminals to America before the practice ceased in 1776. The criminals were sold by jailers to shipping contractors, who then sold them to plantation owners. The criminal was forced to work for the plantation owner for the duration of their sentence. :5 The loss of America as a colony, Australia became the destination for criminals deported to British colonies. More than 160,000 :1 criminals were transported to Australia between 1787 and 1855.
Deportation in the Holocaust
Nazi policies openly deported homosexuals, Jews, Poles, and Romani from their native places of residence to Nazi concentration camps or extermination camps set up at a considerable distance from their original residences. This was the policy officially known as the " Final Solution ". The historical term "deportation", occurring frequently instead of the religious term Holocaust in various locations, thus means in effect "sent to their deaths" — as distinct from deportations in other times and places. 
Alexander Berkman, Emma Goldman, C.L.R. James, Claudia Jones, Fritz Julius Kuhn, Lucky Luciano, and Anna Sage were all deported from the United States by being arrested and brought to the federal immigration control station on Ellis Island in New York Harbor and, from there, forcibly removed from the United States.
In literature, deportation appears as an overriding theme in the 1935 novel, Strange Passage by Theodore D. Irwin. Films depicting or dealing with fictional cases of deportation are many and varied. Among them are Ellis Island (1936), Exile Express (1939), Five Came Back (1939), Deported (1950), and Gambling House (1951). More recently, Shottas (2002) treated the issue of U.S. deportation to the Caribbean post-1997.
- Jean-Marie Henckaerts in his bookMass Expulsion in Modern International Law and Practicewrote: "As far as deportation is concerned, there is no general feature that clearly sets it apart from expulsion. Both term basically indicate the same phenomenon. [...] The only difference seems to be one of preferential use, expulsion being more an international term while deportation is more used in municipal law. [...] One study [discusses this distinction] but immediately adds that in modern practice both terms have become interchangeable." See Jean-Marie Henckaerts (6 July 1995).. Martinus Nijhoff Pblishers. pp. 5–6. ISBN 90-411-0072-5.
- Henckaerts,Mass Expulsion in Modern International Law and Practice, 1995, pp. 4-5.
- Fong Yue Ting v. United States, 149 U.S. 697, at 709 (1893).
- , p. 27.
- , p. 35.
- electricpulp.com.. www.iranicaonline.org.
- later returned
- Bruce, Frederick Fyvie (1990). The Acts of the Apostles: The Greek Text with Introduction and Commentary. Wm. B. Eerdmans Publishing. p. 117. ISBN 0-8028-0966-9.
- Christensen,The Decline of Iranshahr: Irrigation and Environments in the History of the Middle East, 500 B.C. to A.D. 1500, 1993.
- Convention (IV) relative to the Protection of Civilian Persons in Time of War. Geneva, 12 August 1949. by the ICRC
- Henckaerts,Mass Expulsion in Modern International Law and Practice, 1995, p. 5; Forsythe and Lawson,Encyclopedia of Human Rights, 1996, p. 53-54.
- McKay, "The Federal Deportation Campaign in Texas: Mexican Deportation from the Lower Rio Grande Valley During the Great Depression",Borderlands Journal, Fall 1981; Balderrama and Rodriguez,Decade of Betrayal: Mexican Repatriation in the 1930s, 1995; Valenciana, "Unconstitutional Deportation of Mexican Americans During the 1930s: A Family History and Oral History",Multicultural Education, Spring 2006.
- See Albert G. Mata, "Operation Wetback: The Mass Deportation of Mexican Undocumented Workers in 1954 by Juan Ramon García",Contemporary Sociology, 1:5 (September 1983), p. 574 ("the widespread concern and hysteria about 'wetback inundation'..."); Bill Ong Hing,Defining America Through Immigration Policy, Temple University Press, 2004, p. 130. ISBN 1-59213-233-2 ("While Operation Wetback temporarily relieved national hysteria, criticism of the Bracero program mounted."); David G. Gutiérrez,Walls and Mirrors: Mexican Americans, Mexican Immigrants, and the Politics of Ethnicity, University of California Press, 1995, p. 168. ISBN 0-520-20219-8 ("The situation was further complicated by the government's active collusion in perpetuating the political powerlessness of ethnic Mexicans by condoning the use of Mexican labor while simultaneously whipping up anti-Mexican hysteria against wetbacks."); Ian F. Haney López,Racism on Trial: The Chicano Fight for Justice, new ed., Belknap Press, 2004, p. 83. ISBN 0-674-01629-7 ("... Operation Wetback revived Depression-era mass deportations. Responding to public hysteria about the 'invasion' of the United States by 'illegal aliens', this campaign targeted large Mexican communities such as East Los Angeles."); Jaime R. Aguila, "Book Reviews: Decade of Betrayal: Mexican Repatriation in the 1930s. By Francisco E. Balderrama and Raymond Rodríguez",Journal of San Diego History, 52:3-4 (Summer-Fall 2006), p. 197. ("Anti-immigrant hysteria contributed to the implementation of Operation Wetback in the mid 1950s....")
- García, Juan Ramon.Operation Wetback: The Mass Deportation of Mexican Undocumented Workers in 1954. Westport, Ct.: Greenwood Publishing Group, 1980. ISBN 0-313-21353-4
- Hing, Bill Ong.Defining America Through Immigration Policy. Philadelphia: Temple University Press, 2004. ISBN 1-59213-232-4
- . New York Daily News. September 1, 2016 . Retrieved 2016-11-15 .
- . www.hrw.org . Retrieved 2017-10-19 .
- . Human Rights Watch. 2016-04-25 . Retrieved 2017-10-19 .
- . www.ice.gov . Retrieved 2017-10-19 .
- See, e.g., Emerich de Vattel,The Law of Nations - Principles of the Law of Nature, Applied to the Conduct and Affairs of Nations and Sovereigns(translated from French), Philadelphia 1856 (Dublin 1792), Book II,
- International Law Commission,Yearbook of the International Law Commission 1996: Report of the Commission to the General Assembly on the Work of Its 48th Session, 2000.
- Fragomen and Bell,Immigration Fundamentals: A Guide to Law and Practice. New York: Practising Law Institute, 1996.
- Dillman,The Roswell Mills and A Civil War Tragedy: Excerpts from Days Gone by in Alpharetta and Roswell, Georgia, 1996; Hitt,Charged with Treason: The Ordeal of 400 Mill Workers During Military Operations in Roswell, Georgia, 1864-1865, 1992.
- In one estimate, based on a report by Lavrenti Beria to Joseph Stalin, 150,000 of 478,479 deported Ingush and Chechen people (or 31.3 percent) died within the first four years of the resettlement. See: Kleveman, Lutz.The New Great Game: Blood and Oil in Central Asia. Jackson, Tenn.: Atlantic Monthly Press, 2003. ISBN 0-87113-906-5. Another scholar puts the number of deaths at 22.7 percent: Extrapolating from NKVD records, 113,000 Ingush and Chechens died (3,000 before deportation, 10,000 during deportation, and 100,000 after resettlement) in the first three years of the resettlement out of 496,460 total deportees. See: Naimark, Norman M.Fires of Hatred: Ethnic Cleansing in Twentieth-Century Europe. Cambridge, Mass.: Harvard University Press, 2001. ISBN 0-674-00994-0. A third source says a quarter of the 650,000 deported Chechens, Ingush, Karachais and Kalmyks died within four years of resettlement. See: Mawdsley, Evan.The Stalin Years: The Soviet Union 1929-1953. Manchester, England: Manchester University Press, 2003. ISBN 0-7190-6377-9. However, estimates of the number of deportees sometimes varies widely. Two scholars estimated the number of Chechen and Ingush deportees at 700,000, which would halve the percentage estimates of deaths. See: Fischer, Ruth and Leggett, John C.Stalin and German Communism: A Study in the Origins of the State Party. Edison, N.J.: Transaction Publishers, 2006. ISBN 0-87855-822-5
- Conquest, Robert.The Nation Killers. New York: Macmillan, 1970. ISBN 0-333-10575-3
- Accessed August 11, 2008; December 2, 2008, at the Wayback Machine.; Jaimoukha, Amjad M.The Chechens: A Handbook. Florence, Ky.: Routledge, 2005. ISBN 0-415-32328-2.
- Pavel Polian. Against Their Will: The History and Geography of Forced Migrations in the USSR. Central European University Press, 2004. p.. ISBN 978-963-9241-68-8.
- Rosefielde, Steven (2009). Red Holocaust. Routledge. p. 83. ISBN 978-0-415-77757-5.
- Naimark, Norman M.Stalin's Genocides (Human Rights and Crimes against Humanity). Princeton University Press, 2010. p. 131. ISBN 0-691-14784-1
- Rosefielde, Steven (2009). Red Holocaust. Routledge. p. 84. ISBN 978-0-415-77757-5.
- J. Rieber, Alfred (2000). Forced Migration in Central and Eastern Europe, 1939-1950. Routledge. p. 90. ISBN 978-0-7146-5132-3.
- , p. 84 fn. 414.
- , p. 114.
- , p. 124.
- , pp. 748–760.
- Deportation is the term commonly used to depict ejecting an individual from a political or legal jurisdiction. It has been used by the press, legal community, historians and sociologists. See, variously, "Lewis Attacks Deportation of Leaders by West Virginia Authorities",The New York Times, July 17, 1921; "The Law of Necessity As Applied in the Bisbee Deportation Case",Arizona Law Review, 1961; Martin,The Corpse On Boomerang Road: Telluride's War on Labor, 1899-1908, 2004; Silverberg, "Citizens' Committees: Their Role in Industrial Conflict",Public Opinion Quarterly, March 1941; Suggs,Colorado's War on Militant Unionism: James H. Peabody and the Western Federation of Miners, 1991; Lindquist and Fraser, "A Sociological Interpretation of the Bisbee Deportation",Pacific Historical Review, November 1968. Deportation has also been used to describe these events by Presidential commissions; see President's Mediation Commission,Report on the Bisbee Deportations, 1918. The U.S. Supreme Court has also referred to forced internal removal as deportation; seeUnited States v. Guest, 383 U.S. 745, (1966), Harlan, concurring in part and dissenting in part, at 766.
- . University of Arizona. 2005.
- Hill, David (2010). 1788 the brutal truth of the first fleet. Random House Australia. ISBN 978-1741668001.
- Daniels,Coming to America: A History of Immigration and Ethnicity in American Life, 2002
- McCaffray and Melancon, p. 171.
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