When morphological and syntactic change are not in sync

This chapter discusses diachronic implications of the idea that there is a correlation between rich verbal agreement marking and verb movement, known as the Rich Agreement Hypothesis (RAH). Focusing on Koeneman and Zeijlstra’s (2014) recent work that aims at reinstating the RAH in its strongest biconditional form, it presents a set of diachronic case studies that challenge the expectation, fuelled by the strong RAH, that morphological and syntactic change should always go hand in hand. First, it is argued that Koeneman and Zeijlstra’s attempt to accommodate problematic cases (e.g. loss of verbal agreement morphology with delayed loss of verb movement) in terms of syntactic reanalysis runs into difficulties. In addition, the chapter presents data from Lithuanian and Cimbrian, where a change from SOV to SVO resulted in word-order patterns that violate the RAH, an observation that challenges both strong and weak versions of the RAH.