Kaskian (Kaskean) was the language of the Kaskians (Kaska) of northeastern Bronze Age Anatolia in the mountains along the Black Sea coast. The Encyclopedia of Indo-European Culture lists the Kaskians as non–Indo-European.^[2] There are a number of theories regarding the language family to which it belonged.

It is sometimes suspected that Kaskian was related to the pre-Hittite Hattic language, based on toponyms and personal names; the Hattic moon god was named Kasku. Conversely, the Kaskian language may have been an Indo-European language, perhaps related to Thraco-Phrygian.^[3] There may also be connections to the Northwest Caucasian languages; the name Kaskian^[4] may be cognate with an old name for Circassia,^[5] and the name of one of the tribes in the Kaskian confederation, the Abešla, may be cognate with the endonym of the Abkhaz people and some Circassian people,^[6] suggesting the Kaskians proper and Abešla might have been the ancestors of the Circassians and other Caucasian peoples.^[7] It has been conjectured that Kaskian might belong to the Zan family of languages, and have affinities to Megrelian or Laz.^[8]

In 2023, D. Sasseville presented an unknown language preserved on several tablet fragments from the archives of Hattusa and argued on methodological grounds that it is the Kaskean language.^[9]