On the other hand, Sardinian ("sardu") has been the native language of the indigenous Sards ever since Latin supplanted the Pre-Indo-European Paleo-Sardinian, a language supposedly related to Basque with some Berber influence and of which remnants can be still be found in vocabulary and local toponyms. The historical loss of the islanders' political autonomy has kept the language at a stage of dialectal fragmentation, reflecting the coexistence of the various other languages (namely Catalan, Spanish, and finally Italian) imposing themselves in a position of political and thereby social prestige. Because of a movement, described by some authors as a "linguistic and cultural revival" that gained traction in the postwar period, the Sardinians' cultural heritage was recognized in 1997 and 1999, which makes them the largest ethnolinguistic minority group in Italy, with around a million Sardinians still able to speak the language to some degree. However, because of a rigid model of Italian education system that has strongly promoted Italian to the detriment of Sardinian, the language has been in decline over the past century, since the people effectively retaining Sardinian have gradually become a minority in their own island (in fact, most Sardinians are linguistically Italianized nowadays, and it has been estimated that only 10-13 percent of the young native population have some active and passive competence in the language). Therefore, Sardinian is facing challenges analogous to other definitely endangered minority languages across Europe, and its two main Logudorese and Campidanese varieties, as defined by their standard orthographies, have been designated as such by UNESCO.