The toponym "Kartli" first emerges in written accounts in the 5th-century Martyrdom of the Holy Queen Shushanik, the earliest surviving piece of Georgian literature.

The medieval chronicler characteristically renders this name with the Greek nominative suffix –ος (os), as Stephen H. Rapp of Georgia State University (Atlanta) assumes, "in order to impart the account with a sense of antiquity".

[2] The term itself ultimately derives from Proto-Kartvelian root *kart- ("Georgian"), which is considered an ancient inner-Kartvelian formation by modern linguists.

The root kar occurs in numerous placenames across Georgia and, in the opinion of Melikishvili, displays semantic similarity with the Indo-European prototype; cf.

The infiltration of several ancient, chiefly Anatolian, tribes into the territory of modern-day Georgia and their fusion with the autochthons played a decisive role in this process.

This might have been reflected in the story of Arian-Kartli, the semi-legendary place of the aboriginal Georgian habitat found in the early medieval chronicle Conversion of Kartli.

The role of Kartli as a core ethnic and political unit which would form a basis for the subsequent Georgian unification further increased as a result of its Christianization early in the 4th century.

This implied that Persia allowed Kartli or any other region ruled by them to retain a considerable autonomy and the Georgian dynasty of Bagratids to possess the royal throne provided they adopted Islam and remained subordinate to the shah.

Many members of the aristocratic elite of Kartli had important positions in the Persian military and administration and several noble women entered the shah's harems.