Romani people
Most Romani speak one of several dialects of the Romani language, an Indo-Aryan language, with roots in Sanskrit. They also often speak the languages of the countries they live in. Typically, they also incorporate loanwords and calques into Romani from the languages of those countries and especially words for terms that the Romani language does not have. Most of the "Ciganos" of Portugal, the Gitanos of Spain, the Romanichal of the UK, and Scandinavian Travellers have lost their knowledge of pure Romani, and respectively speak the mixed languages Caló, Angloromany, and Scandoromani. Most of the speaker communities in these regions consist of later immigrants from eastern or central Europe.
Boyash
The Boyash are a branch/caste of the Roma who were forced to settle in the 14th century in the Apuseni Mountains, located in Transylvania, and work as slaves in mining (a regionalism for "mine" in Romanian: "baie," from Middle Age Slavonic). Due to their close proximity with the Romanian-speaking people, they lost the use of the Romani language, and started using the Romanian language. Some groups relearned Romani when they came in contact with other Romani-speaking Roma, after they later emigrated from Romania (for example, in Ecuador).