The Roma recognize divisions among themselves based in part on territorial, cultural and dialectal differences. Some authorities recognize five main groups :
- Kalderash (also Kotlar(i) or Căldărari) are the most numerous, traditionally cauldron-making coppersmiths, from the Balkans, many of whom migrated to central Europe and North America;
- Gitanos or Ciganos (also Calé or Calones) mostly in the Iberian Peninsula, North Africa, and southern France; associated with entertainment;
- Sinti (also Sinta), known in German and Dutch as Zigeuner and in Italian as Zingari, mostly in Alsace and other regions of France and Germany (Other experts, and Sinti themselves, insist that Sinti are not a subgroup of Roma but rather a separate ethnic group which also had Indian origins and a history of nomadism);
- Romnichal (also Romanichal or Rom'nies) mainly in Britain and North America;
- Erlides (also Yerlii or Arli) settled in southeastern Europe and Turkey.
Some groups, like the Finnish Roma population (Kaalee) and the Norwegian and Swedish Travellers, are hard to categorize. Each of these main divisions may be further divided into two or more subgroups distinguished by occupational specialization, territorial origin, or both. Some of these group names are Bashaldé; Churari; Luri; Ungaritza; Lovari (Lovara) from Hungary; Lyuli (Jughi, Multani, Luli, Mug(h)at) from Central Asia; Machvaya (Machavaya, Machwaya, or Macwaia) from Serbia; Romungro (Modyar or Modgar) from Hungary and neighbouring carpathian countries; Xoraxai (Horahane) from Greece/Turkey; Boyash (Lingurari, Ludar, Ludari, Rudari, or Zlătari) from Romanian/Moldovan miners; Ursari from Romanian/Moldovan bear-trainers; Argintari from silversmiths; Aurari from goldsmiths; Florari from florists;, and Lăutari from singers.
The absence of a written history has meant that the origin and early history of the Roma people was long an enigma. As early as 200 years ago, cultural scholars hypothesised an Indian origin of the Roma based on linguistic evidence . Genetic information confirms this.
Although the Nazis claimed that the Gypsies were not Aryan, some members of the Gypsy Lore Society (established in 1888 in England) claimed that the Gypsies were the most ancient Aryans and "sought to protect them from mixing with non-Gypsy elements and from modernization...
Until the mid to late eighteenth century, theories of the origin of the Roma were mostly speculative. Then in 1782, Johann Christian Christoph Rüdiger published his research that pointed out the relationship between the Romani language and Hindustani . Subsequent work supported the hypothesis that Romani shared a common origin with the Indo-Aryan languages of Northern India , with Romani grouping most closely with Sinhalese in a recent study.
The majority of historians accepted this as evidence of an Indian origin for the Roma, but some maintained that the Roma acquired the language through contact with Indian merchants.