Caste is a form of social stratification characterized by endogamy, hereditary transmission of a style of life which often includes an occupation, ritual status in a hierarchy, and customary social interaction and exclusion based on cultural notions of purity and pollution.^[1][2] Its paradigmatic ethnographic example is the division of India's Hindu society into rigid social groups, with roots in India's ancient history and persisting to the present time.^[3] However, the economic significance of the caste system in India has been declining as a result of urbanization and affirmative action programs. A subject of much scholarship by sociologists and anthropologists, the Hindu caste system is sometimes used as an analogical basis for the study of caste-like social divisions existing outside Hinduism and India. The term "caste" is also applied to morphological groupings in female populations of ants and bees.^[4]

The English word "caste" derives from the Spanish and Portuguese casta, which, according to the John Minsheu's Spanish dictionary (1569), means "race, lineage, tribe or breed".^[5] When the Spanish colonized the New World, they used the word to mean a "clan or lineage". It was, however, the Portuguese who first employed casta in the primary modern sense of the English word 'caste' when they applied it to the thousands of endogamous, hereditary Indian social groups they encountered upon their arrival in India in 1498.^[5][6] The use of the spelling "caste", with this latter meaning, is first attested in English in 1613.^[5]

Modern India's caste system is based on the artificial superimposition of a four-fold theoretical classification called the Varna on the natural social groupings called the Jāti. From 1901 onwards, for the purposes of the Decennial Census, the British classified all Jātis into one or the other of the Varna categories as described in ancient texts. Herbert Hope Risley, the Census Commissioner, noted that "The principle suggested as a basis was that of classification by social precedence as recognized by native public opinion at the present day, and manifesting itself in the facts that particular castes are supposed to be the modern representatives of one or other of the castes of the theoretical Indian system."^[7] The system of Varnas propounded in ancient Hindu texts envisages the society divided into four classes: Brahmins (scholars and yajna priests), Kshatriyas (rulers and warriors), Vaishyas (farmers, merchants and artisans) and Shudras (workmen/service providers). The texts do not mention any separate, untouchable category in Varna classification. Scholars believe that the Varnas system was never truly operational in society and there is no evidence of it ever being a reality in Indian history. The practical division of the society had always been in terms of Jātis (birth groups), which are not based on any specific principle, but could vary from ethnic origins to occupations to geographic areas. The Jātis have been endogamous groups without any fixed hierarchy but subject to vague notions of rank articulated over time based on lifestyle and social, political or economic status. Many of India's major empires and dynasties like the Mauryas,^[8] Shalivahanas,^[9] Chalukyas,^[10] Kakatiyas^[11] among many others, were founded by people who would have been classified as Shudras, under the Varnas system. It is well established that by the 9th century, kings from all the four castes, including Brahmins and Vaishyas, had occupied the highest seat in the monarchical system in Hindu India, contrary to the Varna theory.^[12] In many instances, as in Bengal, historically the kings and rulers had been called upon, when required, to mediate on the ranks of Jātis, which might number in thousands all over the subcontinent and vary by region. In practice, the jātis may or may not fit into the Varna classes and many prominent Jatis, for example the Jats and Yadavs, straddled two Varnas i.e. Kshatriyas and Vaishyas, and the Varna status of Jātis itself was subject to articulation over time.

Starting with the British colonial Census of 1901 led by Herbert Hope Risley, all the jātis were grouped under the theoretical varnas categories.^[13] According to political scientist Lloyd Rudolph, Risley believed that varna, however ancient, could be applied to all the modern castes found in India, and "[he] meant to identify and place several hundred million Indians within it."^[14] In an effort to arrange various castes in order of precedence functional grouping was based less on the occupation that prevailed in each case in the present day than on that which was traditional with it, or which gave rise to its differentiation from the rest of the community. "This action virtually removed Indians from the progress of history and condemned them to an unchanging position and place in time. In one sense, it is rather ironic that the British, who continually accused the Indian people of having a static society, should then impose a construct that denied progress"^[15] The terms varna (conceptual classification based on occupation) and jāti (groups) are two distinct concepts: while varna is the idealised four-part division envisaged by the Twice-Borns, jāti (community) refers to the thousands of actual endogamous groups prevalent across the subcontinent. The classical authors scarcely speak of anything other than the varnas, as it provided a convenient shorthand; but a problem arises when even Indologists sometimes confuse the two.^[16] Thus, starting with the 1901 Census, Caste officially became India's essential institution, with an imprimatur from the British administrators, augmenting a discourse that had already dominated Indology. “Despite India's acquisition of formal political independence, it has still not regained the power to know its own past and present apart from that discourse”.^[17]

Upon independence from Britain, the Indian Constitution listed 1,108 castes across the country as Scheduled Castes in 1950, for positive discrimination.^[18] The Untouchable communities are sometimes called Scheduled Castes, Dalit or Harijan in contemporary literature.^[19] In 2001, Dalits were 16.2% of India's population.^[20] Most of the 15 million bonded child workers are from the lowest castes.^[21][22]

Independent India has witnessed caste-related violence. In 2005, government recorded approximately 110,000 cases of reported violent acts, including rape and murder, against Dalits.^[23] For 2012, the government recorded 651 murders, 3,855 injuries, 1,576 rapes, 490 kidnappings, and 214 cases of arson.^[24]

The socio-economic limitations of the caste system are reduced due to urbanization and affirmative action. Nevertheless, the caste system still exists in endogamy and patrimony, and thrives in the politics of democracy, where caste provides ready made constituencies to politicians. The globalization and economic opportunities from foreign businesses has influenced the growth of India's middle-class population. Some members of the Chhattisgarh Potter Caste Community (CPCC) are middle-class urban professionals and no longer potters unlike the remaining majority of traditional rural potter members. The co-existence of the middle-class and traditional members in the CPCC has created intersectionality between caste and class.^[25] There is persistence of caste in Indian politics. Caste associations have evolved into caste-based political parties. Political parties and the state perceive caste as an important factor for mobilization of people and policy development.^[26]

Studies by Bhatt and Beteille have shown changes in status, openness, mobility in the social aspects of Indian society. As a result of the modern social pressures on the country, India is experiencing a change in their social sphere dynamic as well as economically in the caste system.^[27] While arranged marriages are still the most common practice in India, the internet has provided a network for younger Indians to take control of their relationships through the use of dating apps. This remains isolated to informal terms, as marriage is not often achieved through the use of these apps.^[28] Hypergamy is still a common practice in India and Hindu culture. Men are expected to marry within their caste, or one below, with no social repercussions. If a woman marries into a higher caste, then her children will take the status of their father. If she marries down, her family is reduced to the social status of their son in law. In this case, the women are bearers of the egalitarian principle of the marriage. There would be no benefit in marrying a higher caste if the terms of the marriage did not imply equality.^[29] However, men are systematically shielded from the negative implications of the agreement.

Geographical factors also determine adherence to the caste system. Many Northern villages are more likely to participate in exogamous marriage, due to a lack of eligible suitors within the same caste. Women in North India have been found to be less likely to leave or divorce their husbands since they are of a relatively lower caste system, and have higher restrictions on their freedoms. On the other hand, Pahari women, of the northern mountains, have much more freedom to leave their husbands without stigma. This often leads to better husbandry as his actions are not protected by social expectations.^[30]

Chiefly among the factors influencing the rise of exogamy is the rapid urbanisation in India experienced over the last century. It is well known that urban centers tend to be less reliant on tradition and are more progressive as a whole. As India’s cities boomed in population, the job market grew to keep pace. Prosperity and stability were now more easily attained by an individual, and the anxiety to marry quickly and effectively was reduced as traditional marriage was viewed as a means to attain these principles. Thus, younger, more progressive generations of urban Indians are less likely than ever to participate in the antiquated system of arranged endogamy.

India has also experimented with Affirmative Action, locally known as “reservation groups”. Quota system jobs, as well as placements in publicly funded colleges, hold spots for the 8% of India’s minority, and underprivileged groups. As a result, in states such as Tamil Nadu or those in the north-east, where underprivileged populations predominate, over 80% of government jobs are set aside in quotas. In education, colleges lower the marks necessary for the Dalits to enter.^[31]

The Nepalese caste system resembles that of the Indian jāti system with numerous jāti divisions with a varna system superimposed for a rough equivalence. But since the culture and the society is different some of the things are different. Inscriptions attest the beginnings of a caste system during the Licchavi period. Jayasthiti Malla (1382–1395) categorized Newars into 64 castes (Gellner 2001). A similar exercise was made during the reign of Mahindra Malla (1506–1575). The Hindu social code was later set up in Gorkha by Ram Shah (1603–1636).

McKim Marriott claims a social stratification that is hierarchical, closed, endogamous and hereditary is widely prevalent, particularly in western parts of Pakistan. Frederik Barth in his review of this system of social stratification in Pakistan suggested that these are castes.^[32][33][34]

The caste system in Sri Lanka is a division of society into strata,^[35] influenced by the textbook varnas and jāti system found in India. Ancient Sri Lankan texts such as the Pujavaliya, Sadharmaratnavaliya and Yogaratnakaraya and inscriptional evidence show that the above hierarchy prevailed throughout the feudal period. The repetition of the same caste hierarchy even as recently as the 18th century, in the British/Kandyan period Kadayimpoth – Boundary books as well, indicates the continuation of the tradition right up to the end of Sri Lanka's monarchy.

Balinese caste structure has been described in early 20th-century European literature to be based on three categories – triwangsa (thrice born) or the nobility, dwijāti (twice born) in contrast to ekajāti (once born) the low folks. Four statuses were identified in these sociological studies, spelled a bit differently from the caste categories for India:^[36]

The Brahmana caste was further subdivided by these Dutch ethnographers into two: Siwa and Buda. The Siwa caste was subdivided into five: Kemenuh, Keniten, Mas, Manuba and Petapan. This classification was to accommodate the observed marriage between higher-caste Brahmana men with lower-caste women. The other castes were similarly further sub-classified by these 19th-century and early-20th-century ethnographers based on numerous criteria ranging from profession, endogamy or exogamy or polygamy, and a host of other factors in a manner similar to castas in Spanish colonies such as Mexico, and caste system studies in British colonies such as India.^[36]

In the Philippines, pre-colonial societies do not have a single social structure. The class structures can be roughly categorized into four types:^[37]

During the period of Yuan Dynasty, ruler Kublai Khan enforced a Four Class System, which was a legal caste system. The order of four classes of people was maintained by the information of the descending order were:

Today, the Hukou system is considered by various sources as the current caste system of China.^[40][41][42]

There is also significant controversy over the social classes of Tibet, especially with regards to the serfdom in Tibet controversy.

In Japan's history, social strata based on inherited position rather than personal merit, were rigid and highly formalized in a system called mibunsei (身分制). At the top were the Emperor and Court nobles (kuge), together with the Shōgun and daimyō. Below them, the population was divided into four classes: samurai, peasants, craftsmen and merchants. Only samurai were allowed to bear arms. A samurai had a right to kill any peasants, craftsman or merchant who he felt were disrespectful. Merchants were the lowest caste because they did not produce any products. The castes were further sub-divided; for example, peasants were labelled as furiuri, tanagari, mizunomi-byakusho among others. As in Europe, the castes and sub-classes were of the same race, religion and culture.

Howell, in his review of Japanese society notes that if a Western power had colonized Japan in the 19th century, they would have discovered and imposed a rigid four-caste hierarchy in Japan.^[43]

De Vos and Wagatsuma observe that Japanese society had a systematic and extensive caste system. They discuss how alleged caste impurity and alleged racial inferiority, concepts often assumed to be different, are superficial terms, and are due to identical inner psychological processes, which expressed themselves in Japan and elsewhere.^[44]

Endogamy was common because marriage across caste lines was socially unacceptable.^[44][45]

Japan had its own untouchable caste, shunned and ostracized, historically referred to by the insulting term Eta, now called Burakumin. While modern law has officially abolished the class hierarchy, there are reports of discrimination against the Buraku or Burakumin underclasses.^[46] The Burakumin are regarded as "ostracised".^[47] The burakumin are one of the main minority groups in Japan, along with the Ainu of Hokkaidō and those of residents of Korean and Chinese descent.

The baekjeong (백정) were an "untouchable" outcaste of Korea. The meaning today is that of butcher. It originates in the Khitan invasion of Korea in the 11th century. The defeated Khitans who surrendered were settled in isolated communities throughout Goryeo to forestall rebellion. They were valued for their skills in hunting, herding, butchering, and making of leather, common skill sets among nomads. Over time, their ethnic origin was forgotten, and they formed the bottom layer of Korean society.

In 1392, with the foundation of the Confucian Joseon dynasty, Korea systemised its own native class system. At the top were the two official classes, the Yangban, which literally means "two classes". It was composed of scholars (munban) and warriors (muban). Scholars had a significant social advantage over the warriors. Below were the jung-in (중인-中人: literally "middle people". This was a small class of specialized professions such as medicine, accounting, translators, regional bureaucrats, etc. Below that were the sangmin (상민-常民: literally 'commoner'), farmers working their own fields. Korea also had a serf population known as the nobi. The nobi population could fluctuate up to about one third of the population, but on average the nobi made up about 10% of the total population.^[48] In 1801, the vast majority of government nobi were emancipated,^[49] and by 1858 the nobi population stood at about 1.5% of the total population of Korea.^[50] The hereditary nobi system was officially abolished around 1886–87 and the rest of the nobi system was abolished with the Gabo Reform of 1894,^[50] but traces remained until 1930.

The opening of Korea to foreign Christian missionary activity in the late 19th century saw some improvement in the status of the baekjeong. However, everyone was not equal under the Christian congregation, and even so protests erupted when missionaries tried to integrate baekjeong into worship, with non-baekjeong finding this attempt insensitive to traditional notions of hierarchical advantage. Around the same time, the baekjeong began to resist open social discrimination.^[51] They focused on social and economic injustices affecting them, hoping to create an egalitarian Korean society. Their efforts included attacking social discrimination by upper class, authorities, and "commoners", and the use of degrading language against children in public schools.^[52]

With the Gabo reform of 1896, the class system of Korea was officially abolished. Following the collapse of the Gabo government, the new cabinet, which became the Gwangmu government after the establishment of the Korean Empire, introduced systematic measures for abolishing the traditional class system. One measure was the new household registration system, reflecting the goals of formal social equality, which was implemented by the loyalists' cabinet. Whereas the old registration system signified household members according to their hierarchical social status, the new system called for an occupation.^[53]

While most Koreans by then had surnames and even bongwan, although still substantial number of cheonmin, mostly consisted of serfs and slaves, and untouchables did not. According to the new system, they were then required to fill in the blanks for surname in order to be registered as constituting separate households. Instead of creating their own family name, some cheonmins appropriated their masters' surname, while others simply took the most common surname and its bongwan in the local area. Along with this example, activists within and outside the Korean government had based their visions of a new relationship between the government and people through the concept of citizenship, employing the term inmin ("people") and later, kungmin ("citizen").^[53]

The Committee for Human Rights in North Korea reported that "Every North Korean citizen is assigned a heredity-based class and socio-political rank over which the individual exercises no control but which determines all aspects of his or her life."^[54] Regarded as Songbun, Barbara Demick describes this "class structure" as an updating of the hereditary "caste system", combining Confucianism and Stalinism.^[55] She claims that a bad family background is called "tainted blood", and that by law this "tainted blood" lasts for three generations.^[56]

Heidi Fjeld has put forth the argument that pre-1950s Tibetan society was functionally a caste system, in contrast to previous scholars who defined the Tibetan social class system as similar to European feudal serfdom, as well as non-scholarly western accounts which seek to romanticize a supposedly 'egalitarian' ancient Tibetan society.

Yezidi society is hierarchical. The secular leader is a hereditary emir or prince, whereas a chief sheikh heads the religious hierarchy. The Yazidi are strictly endogamous; members of the three Yazidi castes, the murids, sheikhs and pirs, marry only within their group.

Pre-Islamic Sassanid society was immensely complex, with separate systems of social organization governing numerous different groups within the empire.^[57] Historians believe society comprised four^[58][59][60] social classes:

In Yemen there exists a hereditary caste, the African-descended Al-Akhdam who are kept as perennial manual workers. Estimates put their number at over 3.5 million residents who are discriminated, out of a total Yemeni population of around 22 million.^[61]

Various sociologists have reported caste systems in Africa.^[62][63][64] The specifics of the caste systems have varied in ethnically and culturally diverse Africa, however the following features are common – it has been a closed system of social stratification, the social status is inherited, the castes are hierarchical, certain castes are shunned while others are merely endogamous and exclusionary.^[65] In some cases, concepts of purity and impurity by birth have been prevalent in Africa. In other cases, such as the Nupe of Nigeria, the Beni Amer of East Africa, and the Tira of Sudan, the exclusionary principle has been driven by evolving social factors.^[66]

Among the Igbo of Nigeria – especially Enugu, Anambra, Imo, Abia, Ebonyi, Edo and Delta states of the country – Obinna finds Osu caste system has been and continues to be a major social issue. The Osu caste is determined by one's birth into a particular family irrespective of the religion practised by the individual. Once born into Osu caste, this Nigerian person is an outcast, shunned and ostracized, with limited opportunities or acceptance, regardless of his or her ability or merit. Obinna discusses how this caste system-related identity and power is deployed within government, Church and indigenous communities.^[62]

The osu class systems of eastern Nigeria and southern Cameroon are derived from indigenous religious beliefs and discriminate against the "Osus" people as "owned by deities" and outcasts.

The Songhai economy was based on a caste system. The most common were metalworkers, fishermen, and carpenters. Lower caste participants consisted of mostly non-farm working immigrants, who at times were provided special privileges and held high positions in society. At the top were noblemen and direct descendants of the original Songhai people, followed by freemen and traders.^[67]

In a review of social stratification systems in Africa, Richter reports that the term caste has been used by French and American scholars to many groups of West African artisans. These groups have been described as inferior, deprived of all political power, have a specific occupation, are hereditary and sometimes despised by others. Richter illustrates caste system in Ivory Coast, with six sub-caste categories. Unlike other parts of the world, mobility is sometimes possible within sub-castes, but not across caste lines. Farmers and artisans have been, claims Richter, distinct castes. Certain sub-castes are shunned more than others. For example, exogamy is rare for women born into families of woodcarvers.^[68]

Similarly, the Mandé societies in Gambia, Ghana, Guinea, Ivory Coast, Liberia, Senegal and Sierra Leone have social stratification systems that divide society by ethnic ties. The Mande class system regards the jonow slaves as inferior. Similarly, the Wolof in Senegal is divided into three main groups, the geer (freeborn/nobles), jaam (slaves and slave descendants) and the underclass neeno. In various parts of West Africa, Fulani societies also have class divisions. Other castes include Griots, Forgerons, and Cordonniers.

Tamari has described endogamous castes of over fifteen West African peoples, including the Tukulor, Songhay, Dogon, Senufo, Minianka, Moors, Manding, Soninke, Wolof, Serer, Fulani, and Tuareg. Castes appeared among the Malinke people no later than 14th century, and was present among the Wolof and Soninke, as well as some Songhay and Fulani populations, no later than 16th century. Tamari claims that wars, such as the Sosso-Malinke war described in the Sunjata epic, led to the formation of blacksmith and bard castes among the people that ultimately became the Mali empire.

As West Africa evolved over time, sub-castes emerged that acquired secondary specializations or changed occupations. Endogamy was prevalent within a caste or among a limited number of castes, yet castes did not form demographic isolates according to Tamari. Social status according to caste was inherited by off-springs automatically; but this inheritance was paternal. That is, children of higher caste men and lower caste or slave concubines would have the caste status of the father.^[64]

Ethel M. Albert in 1960 claimed that the societies in Central Africa were caste-like social stratification systems.^[69] Similarly, in 1961, Maquet notes that the society in Rwanda and Burundi can be best described as castes.^[70] The Tutsi, noted Maquet, considered themselves as superior, with the more numerous Hutu and the least numerous Twa regarded, by birth, as respectively, second and third in the hierarchy of Rwandese society. These groups were largely endogamous, exclusionary and with limited mobility.^[71]

In a review published in 1977, Todd reports that numerous scholars report a system of social stratification in different parts of Africa that resembles some or all aspects of caste system. Examples of such caste systems, he claims, are to be found in Ethiopia in communities such as the Gurage and Konso. He then presents the Dime of Southwestern Ethiopia, amongst whom there operates a system which Todd claims can be unequivocally labelled as caste system. The Dime have seven castes whose size varies considerably. Each broad caste level is a hierarchical order that is based on notions of purity, non-purity and impurity. It uses the concepts of defilement to limit contacts between caste categories and to preserve the purity of the upper castes. These caste categories have been exclusionary, endogamous and the social identity inherited.^[73] Alula Pankhurst has published a study of caste groups in SW Ethiopia.^[74]

Among the Kafa, there were also traditionally groups labeled as castes. "Based on research done before the Derg regime, these studies generally presume the existence of a social hierarchy similar to the caste system. At the top of this hierarchy were the Kafa, followed by occupational groups including blacksmiths (Qemmo), weavers (Shammano), bards (Shatto), potters, and tanners (Manno). In this hierarchy, the Manjo were commonly referred to as hunters, given the lowest status equal only to slaves."^[75]

The Borana Oromo of southern Ethiopia in the Horn of Africa also have a class system, wherein the Wata, an acculturated hunter-gatherer group, represent the lowest class. Though the Wata today speak the Oromo language, they have traditions of having previously spoken another language before adopting Oromo.^[76]

The traditionally nomadic Somali people are divided into clans, wherein the Rahanweyn agro-pastoral clans and the occupational clans such as the Madhiban were traditionally sometimes treated as outcasts.^[77] As Gabboye, the Madhiban along with the Yibir and Tumaal (collectively referred to as sab) have since obtained political representation within Somalia, and their general social status has improved with the expansion of urban centers.^[72]

For centuries, through the modern times, the majority regarded Cagots who lived primarily in the Basque region of France and Spain as an inferior caste, the untouchables. While they had the same skin color and religion as the majority, in the churches they had to use segregated doors, drink from segregated fonts, and receive communion on the end of long wooden spoons. It was a closed social system. The socially isolated Cagots were endogamous, and chances of social mobility non-existent.^[78][79]

In July 2013, the UK government announced its intention to amend the Equality Act 2010 to "introduce legislation on caste, including any necessary exceptions to the caste provisions, within the framework of domestic discrimination law".^[80] Section 9(5) of the Equality Act 2010 provides that "a Minister may by order amend the statutory definition of race to include caste and may provide for exceptions in the Act to apply or not to apply to caste".

From September 2013 to February 2014, Meena Dhanda led a project on "Caste in Britain" for the UK Equality and Human Rights Commission (EHRC).^[81]

In view of W. Lloyd Warner, the relationship between Blacks and Whites in the US historically showed many features of caste like residential segregation, marriage restrictions.^[82] Discrimination based upon socio-economic factors are historically prevalent within the country.

According to Gerald D. Berreman, in the two systems, there are rigid rules of avoidance and certain types of contacts are defined as contaminating. In India, there are complex religious features which make up the system, whereas in the United States race and color are the basis of differentiation. The caste system in India and the United States has higher groups which desire to retain their position for themselves and thus perpetuate the system.^[83]

The process of creating a homogenized society by social engineering in both India and the US has created other institutions that have made class distinctions among groups evident. Anthropologist James C. Scott elaborates on how “global capitalism is perhaps the most powerful force for homogenization, whereas the state may in some instances be the defender of local difference and variety.”^[84] The caste system further emphasizes differences between the socio-economic classes that arise as a product of capitalism, which makes social mobility more difficult. Parts of the United States are sometimes divided by race and class status despite the national narrative of integration.

As a result of increased immigration to the United States, many Indian Americans have brought traditional caste values to the United States. A survey commissioned by Equality Labs finds that caste discrimination is also playing out in the United States. 2/3 of the members of the lowest caste, called Dalits, said that they have faced workplace discrimination due to their caste. 41% have experienced discrimination in education because the caste system is now being practiced in the United States.^[85]