Latgalian language
Originally Latgalians were a tribe living in modern Vidzeme and Latgale. It is thought that they spoke the Latvian language, which later spread through the rest of modern Latvia, absorbing features of the Old Curonian, Semigallian, Selonian and Livonian languages. The Latgale area became politically separated during the Polish–Swedish wars, remaining part of the Polish–Lithuanian Commonwealth as the Inflanty Voivodeship, while the rest of Latvians lived in lands dominated by Baltic German nobility. Both centuries of separate development and the influence of different prestige languages likely contributed to the development of modern Latgalian as distinct from the language spoken in Vidzeme and other parts of Latvia.
Latvian language
The adoption of Latvian by minorities was brought about by its status as the only official language of the country, its prominence in the education system, its sole use in the public sector and by changes in the society after the fall of the Soviet Union that shifted linguistic focus away from Russian. As an example, in 2007 universities and colleges for the first time received applications from prospective students who had a bilingual secondary education in schools for minorities. Fluency in Latvian is expected in a variety of professions and careers.