The Jász are a Hungarian subgroup of Eastern Iranic descent who have lived in Hungary since the 13th century. They live mostly in a region known as Jászság, which comprises the north-western part of Jász-Nagykun-Szolnok county. They are sometimes known in English by the exonym Jassic and are also known by the endonyms Iasi and Jassy. They originated as a nomadic Alanic people from the Pontic steppe.

Hungarians, also known as Magyars, are a Central European nation and an ethnic group native to Hungary and historical Hungarian lands who share a common culture, history, ancestry, and language. The Hungarian language belongs to the Uralic language family, alongside, most notably Finnish and Estonian.