Switch Reference 2.0

The paper describes the switch-reference system of Aguaruna, a Jivaroan language spoken in north Peru. This language has two formally distinct subsystems, one marking canonical same/different subject, the other marking coreference relations involving both subjects and non-subjects. Historical evidence is presented to show that the development of these two systems involved oblique (locative) and core (nominative and accusative) case marking respectively, and cross-linguistic parallels involving t