Nagyatád was established during the Hungarian conquest by the "Horka" tribe. However this region was already inhabited in prehistoric times. It was first mentioned in 1190 in official documents. At that time the settlement was situated at the northern part of today's Nagyatád. It was also mentioned in 1382 as "Populi et cives in villa Athad" and was part of "Segesd County". It was of Queen Elizabeth, later it belonged to the "Anthimi" then to the Batthyány family. In 1395 "György Kis de Kővágóörs" got the village. But in 1403 it was already in the hands of "János Anthimi". It got market town rights in 1475 from Matthias Corvinus and therefore it became an important commercial centre. "Boldizsár Batthyány" and "András Alapi" owned the settlement in 1475. In 1550 it belonged to "Kristóf Batthyány". Thanks to its favorable location vivid trade flourished there until the Turkish occupation when it almost perished. According to the Turkish tax register there were only 8 households in 1554. Between 1565 and 1571 it listed just 12 houses. Meanwhile, the Hungarian nobles still claimed it as their territory. In 1573 "Pál Czindery" owned it. Between 1598 and 1599 "Kristóf Pethő" was its owner. According to the tithe register of the Pannonhalma Archabbey the settlement was divided in to parts, "Atád" and "Kis-Atád" () and belonged to the Diocese of Székesfehérvár.