The Tat language, also known as Caucasian Persian, Tat/Tati Persian, or Caucasian Tat, is a Southwestern Iranian language closely related to, but not fully mutually intelligible with Persian and spoken by the Tats in Azerbaijan and Russia. There is also an Iranian language called Judeo-Tat spoken by Jews of Caucasus. General information The Tats are an indigenous Iranian people in the Caucasus who trace their origin to the Sassanid-period migrants from Iran (ca. fifth century AD). Tat is endangered, classified as "severely endangered" by UNESCO's Atlas of the World's Languages in Danger. Most scholars divide Tat into two general varieties: Jewish and Muslim, with religious differences correlating with linguistic differences. Another, almost extinct, variety of Tat is spoken by Christians of Armenian origin, who are called Armeno-Tats. Dialects Vladimir Minorsky mentions in the first edition of Encyclopaedia of Islam that like most Persian dialects, Tati is not very regular in its characteristics, and occupies a position between modern Persian and the Caspian dialects. According to him, The Great Russian Encyclopedia of 1901 gives the number of Tati speakers in 1901 as 135,000. In the 1930s, Minorsky estimated the number of Tati speakers to be 90,000 and the decrease to be the result of gradual Turkicization. Variants Aruskush-Daqqushchu Lahyj Balakhani Devechi Qyzyl Qazma Qonaqkend Absheron Surakhani Northern Tats Malham Quba Speakers According to the 1989 Soviet census, 30,000 Tats lived in the Soviet Union, of which 10,000 were in Azerbaijan. Not all likely speak Tati, and this does not include the more rural locations that were not reached by the census. It is vital to stress that the Tats are one of the most assimilated of Azerbaijan’s ethnic groups. This is particularly true for urban Tats. All of this makes it difficult to identify the true number of the Tat ethnic group. The adults in most of the mountain and foothill communities reported they use Tat as their main language of interaction. They speak Tat with each other, but speak Azerbaijani with their children so that they will learn the language before beginning school. If the wife in the family is non-Tat speaking, however, the family is most likely to use Azerbaijani in the home. In the villages of Lahıc and Zǝyvǝ, women who marry in are reported to learn Tat. Ethnic population Research has demonstrated that the word “Tat” does not have an ethnic origin. This is the term the