Languages spoken in contiguous areas tend to have similar systems of evidentiality marking. The Caucasus is part of a large area where systems centered on marking events as not witnessed by the speaker are widespread among genealogically unrelated languages. It is often suggested that Turkic languages could be the source of diffusion in this case, because evidentiality is an old and prominent feature of Turkic grammar. This paper explores the areal dimension of evidentiality in languages of the East Caucasian family, which are spoken on a relatively compact territory in the eastern Caucasus. It provides an overview of the most common types of marking and their geographical distribution among the East Caucasian languages and their Turkic neighbors. The spread of evidentiality as part of the tense system shows a peculiar pattern in the eastern Caucasus, which suggests that it could be a contact-induced feature. However, a number of factors prevent the reconstruction of a specific borrowing scenario. Based on the currently available data the Turkic contact hypothesis cannot be confirmed nor refuted. The paper proposes an alternative scenario for a mixed language-internal and contact-induced development that can possibly be verified with data from oral narratives.