Loss of ergativity in Eastern Indo-Aryan languages

Abstract Old Eastern Indo-Aryan stage/OEIA (900–1100 AD approx) showed split ergativity with evidence from its sole source Caryapada . New Eastern Indo-Aryan/EIA languages have lost their ergative properties ( Stump, 1983 ; Bubenik, 1989 , among others) gradually, evolving as nominative-accusative languages in the present time. The current study highlights how the Voice head in the structure is responsible for the evolution of the case system in the EIA languages. As the Voice head is intricately related to the external theta role and ergative case ( Legate, 2014 ), it is essential to note its characteristics in the diachrony of EIA languages. This paper proposes that OEIA ergativity, seen in Caryapada , is DP-ergative, following the diagnostics of Polinsky (2016) , where the Voice head assigns structural ergative to subject DP. It entails that OEIA has a distinct Voice head in its spine, which assigns the structural ergative case to the DP. The diagnostics used are agreement, A-movement, A′ movement, Binding, and coordinate structures. However, such split ergativity is not seen in the present EIA languages. This entails that the Voice head is lost. This loss led to the rise of a TP-determined structure for all tenses, leading to the emergence of the nominative alignment.