Diachronic evolution of the subordinator kak in Russian

In Russian, the subordinator kak ‘how’ is both a manner question word and an eventive complementizer. The Russian linguistic tradition explains the colexification of the two functions in terms of a semantic shift from manner as characteristic of a situation to event description as a whole. Alternatively, a grammaticalization scenario from manner complements to event/propositional complements has been suggested: manner complements originally have a propositional frame, which is foregrounded concurrently with the loss of the manner meaning, giving rise to both eventive and propositional interpretations. This article is aimed at testing both hypotheses. We study several large Old Russian manuscripts, starting from the first available documents of the 11th century, and show that at the earliest documented period Old Russian kako/kakъ could be used in all types of complement clauses. It could introduce eventive, propositional, manner and irrealis purposive-like complements. Accordingly, the evolution of the subordinator kak in complementation involves a narrowing of its functional domain. We classify Old Russian texts based on the period and trace the gradual loss of particular functions during the centuries. Thus, we show that the Russian data supports the second grammaticalization scenario.