Mulatto in the context of Cape Verde

Casta (Spanish: [ˈkasta]) is a term which means "lineage" in Spanish and Portuguese and has historically been used as a racial and social identifier. In the context of the Spanish Empire in the Americas, the term also refers to a controversial 20th-century theoretical framework which postulated that colonial society operated under a hierarchical race-based "caste system". From the outset, colonial Spanish America resulted in widespread intermarriage: unions of Spaniards (españoles), indigenous people (indios), and Africans (negros).

Basic mixed-race categories that appeared in official colonial documentation were mestizo, generally offspring of a Spaniard and an Indigenous person; and mulatto, offspring of a Spaniard and an African. A plethora of terms were used for people with mixed Spanish, Indigenous, and African ancestry in 18th-century casta paintings, but they are not known to have been widely used officially or unofficially in the Spanish Empire.

The term multiracial people refers to people who are mixed with two or more races and the term multi-ethnic people refers to people who are of more than one ethnicity. A variety of terms have been used both historically and presently for multiracial people in a variety of contexts, including multiethnic, polyethnic, occasionally bi-ethnic, biracial, mixed-race, Métis, Muwallad, Melezi, Coloured, Dougla, half-caste, ʻafakasi, mulatto, mestizo, mutt, Melungeon, quadroon, octoroon, griffe, sacatra, sambo/zambo, Eurasian, hapa, hāfu, Garifuna, pardo, and Gurans. A number of these once-acceptable terms are now considered offensive, in addition to those that were initially coined for pejorative use.

Individuals of multiracial backgrounds make up a significant portion of the population in many parts of the world. In North America, studies have found that the multiracial population is continuing to grow. In many countries of Central and South America, mestizos make up the majority of the population (Panama, Bolivia, Peru, Colombia...) and in some others also mulattoes. In the Caribbean, multiracial people officially make up the majority of the population in the Dominican Republic (73%) and Aruba (68%).

Spanish Argentines (Spanish: hispano-argentinos) are Argentine-born citizens who are predominantly or totally of Spanish descent. The arrival of Spanish emigrants in Argentina took place first in the period before Argentina's independence from Spain, and again in large numbers during the late 19th and early 20th centuries. Between the 15th and 19th centuries, the Spanish Empire was the sole colonial power in the territories that became Argentina after the 1816 Argentine declaration of independence. Thus, before 1850, the vast majority of European settlers in Argentina were from Spain and they carried the Spanish colonial administration, including religious affairs, government, and commercial business. A substantial Spanish descended Criollo population gradually built up in the new cities, while some mixed with the amerindians (Mestizos), with the slave population sub-saharan descended (Mulattoes) or with other European immigrants. Currently, a large part of Argentines can be considered Criollos or Castizos.

Since a great portion of the immigrants to Argentina before the mid-19th century were of Spanish descent, and a significant part of the late-19th century/early-20th century immigrants to Argentina were Spaniards, almost all Argentines are at least partly of Spanish ancestry. Indeed, the 20 most common surnames in Argentina are Spanish. The prevalence and the numerous shared cultural aspects between Argentina and Spain (the Spanish language, Roman Catholicism, Criollo/Hispanic traditions) has been mixed with other European and Latin Mediterranean cultures with the immigration to Argentina during the 20th century. This has led to a hybrid Argentine culture which is among the most distinct from traditional Spanish culture in Latin America. Furthermore, a large proportion of Spanish immigration to Argentina during the 20th century was from the North Western region of Galicia, which has a separate language and distinct culture from other parts of Spain.

Annobonese Creole is a Portuguese creole known to its speakers as Fa d'Ambu or Fá d'Ambô (Portuguese: Fala de Ano-Bom, "Annobón speech"). It is spoken on the Annobón and Bioko Islands off the coast of Equatorial Guinea, mostly by people of mixed African, Portuguese and Spanish descent. It is called annobonense or annobonés in Spanish.

The attitude in Equatorial Guinea towards this language is positive. It is taught in special courses in the capital city of Malabo.

Melungeon (/məˈlʌndʒən/ mə-LUN-jən) (sometimes also spelled Malungean, Melangean, Melungean, Melungin) was a slur historically applied to individuals and families of mixed-race ancestry with roots in colonial Virginia, Tennessee, and North Carolina who were primarily descended from free people of color and white settlers. In the late 20th century, the term was reclaimed by descendants of these families, especially in southern Appalachia. Despite this mixed heritage, many modern Melungeons pass as white, as did many of their ancestors.

Many groups have historically been referred to as Melungeon, including the Melungeons of Newman's Ridge, the Lumbee Tribe of North Carolina, the Chestnut Ridge people, and the Carmel Melungeons. Free people of color in colonial Virginia were predominantly of African and European descent; however, many families also had varying amounts of Native American and East Indian ancestry. Some modern researchers believe that early Atlantic Creole slaves, descended from or acculturated by Iberian lançados and Sephardi Jews fleeing the Inquisition, were one of the precursor populations to these groups. Many creoles, once in British America, were able to obtain their freedom and many married into local white families.