Jassic is a dialect of the Ossetian language and the name of a nomadic tribe settled in Hungary in the 13th century. The Jassic people came to Hungary together with the Cumanians, chased by the Mongol-Tatars. They were admitted by the Hungarian king Béla IV, hoping that they will assist fighting the Mongol-Tatar invasion. But shortly after the entrance, relationship worsened dramatically between the Hungarian nobility and the Cumanian-Jassic tribes and they left the country. After the end of the Mongol-Tatar occupation they returned and were settled in the central part of the Hungarian Plain. A dialect (from the Greek word διάλεκτος) is a variety of a language used by people from a particular geographic area. ... Ossetic or Ossetian is an Iranian language spoken on the slopes of the Caucasus mountains on the borders of Russia and Georgia. ...

Initially, their main occupation was animal husbandry. During the next two centuries they were fully assimilated to the Hungarian population, their language disappeared, but they preserved their Jassic identity. The only literary record of the Jassic language was found in the 1950s in the Hungarian National Széchenyi Library. The language was reconstructed with the help of Ossetian analogies.