Dadiani was a Georgian

Georgia (country)

Georgia is a sovereign state in the Caucasus region of Eurasia. Located at the crossroads of Western Asia and Eastern Europe, it is bounded to the west by the Black Sea, to the north by Russia, to the southwest by Turkey, to the south by Armenia, and to the southeast by Azerbaijan. The capital of...

 family of nobles, dukes and princes, and a ruling dynasty of the western Georgian province of Samegrelo

Samegrelo

Samegrelo/Samargalo or Megrelia, Mingrelia is a historic province in the western part of Georgia, formerly also known as Odishi.It is inhabited by the Megrelians, an ethnic subgroup of the Georgians.-Geography and Climate:...

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The first data about the family dates back to 1046. Presumably, the Dadiani descended from a certain Dadi, of the House of Vardanisdze

House of Vardanisdze

The House of Vardanisdze was an aristocratic family in medieval Georgia, listed among the Great Nobles of the realm.The family is presumed to have branched off from another eminent Georgian feudal clan of the Marushisdze, a hypothesis supported by the abundance of the name Marushiani in the...

. Appointed as hereditary eristavi (dukes) of Odishi (Samegrelo

Samegrelo

Samegrelo/Samargalo or Megrelia, Mingrelia is a historic province in the western part of Georgia, formerly also known as Odishi.It is inhabited by the Megrelians, an ethnic subgroup of the Georgians.-Geography and Climate:...

) in reward for their military services, the family had become the most powerful feudal house in western Georgia

Georgia (country)

Georgia is a sovereign state in the Caucasus region of Eurasia. Located at the crossroads of Western Asia and Eastern Europe, it is bounded to the west by the Black Sea, to the north by Russia, to the southwest by Turkey, to the south by Armenia, and to the southeast by Azerbaijan. The capital of...

 by the 1280s.