An analysis of indirect object passives in English and their development from Late Old English and Early Middle English suggests that their existence is related to the development of double object constructions. As long as the dative and accusative cases had not merged, neither pronominal nor nominal indirect objects required a preposition; however, once the nominal system case collapsed, nominal indirect objects required a preposition to express their function, while pronominal ones did not. This use led to a grammaticalization of the difference between the two classes of direct objects. When the pronominal case system in turn collapsed the accusative and dative endings, this grammaticalized difference between the two kinds of indirect objects remained. However, by the time the case distinction between accusative and dative was lost for pronouns, a bare pronoun had already been established as a possible realization for an indirect object. Examples of direct object passives without a preposition for the indirect object support the conclusion that indirect passives only appeared after the double object construction became a productive alternative to the active construction with a direct object and a prepositional indirect object. (MSE)