The Czech Republic is one of six countries in this database that does not legally have an official language, only a ‘de facto’ one: Czech. Historically, Czech was known as Bohemian and the historical Lands of the Bohemian Crown included Bohemia, Moravia and Czech Silesia. Lower Silesian is still spoken in the Czech Republic today, and Moravian Croatian can be classified as the northernmost variety of Burgenland Croatian. The inclusion of Moravian Croatian in the ECRML was strongly welcomed by the community also as a form of moral rehabilitation, as older generations were forcefully displaced from the Czech borderlands following World War II. There is no precise data on the current number of Moravian Croatians – census data from 2021 not only conflates Moravian Croatians with more recently arrived Croats following the Yugoslav conflict in the 1990s, it was also not mandatory to state a nationality in former censuses, which 25% of the population chose not to do. According to expert estimations, the actual Moravian Croatian community likely consists of only a few hundred persons, rendering their language critically endangered. There is no official national data on the number of deaf people in the Czech Republic and the number of deaf Sign Language users is estimated to be around 10 000. Local languages not established by the chosen sources so far, but spoken by officially recognised Czech national minorities include Belarusian, Bulgarian, Georgian, Greek, Serbian, Ukrainian, and Vietnamese.