Multiple dative-marking grammaticalization: Spanish as a special kind of primary object language

The aim of this paper is to provide some diachronic evidence of how a language acquires primary object properties, and to shed some light on the disputable status of dative expressions (Dats) in two object constructions. Spanish having in its origin two object case-markings, one for the Acc-patient and one for the Dat-recipient, has been progressively acquiring only one object case-marking. This language would have been sliding from a DO–IO language toward a special kind of PO–SO language. This paper examines seven apparently unconnected syntactic changes, showing that a common deep pattern unifies them: a grammaticalization process which reinforces Dat object-marking as a prime argument in the history of Spanish. In various areas of the transitivity system, Dats usurped the grammatical function performed originally by the Acc. As a consequence, a fair distinction between DO and IO does not hold; there are primary object effects in this language.