In this paper, the authoress analyses the Old Hungarian tense system in the framework of Universal Grammar. In this analysis, the OH verb form mond 'says' represents Simple Present, monda 'said' is Simple Past, mondott 'has said' stands for Present Perfect, mond vala 'was saying' is an instance of Past Imperfective, and mondott vala 'had said' is that of Past Perfect. That is, she assumes that -t, -tt was not a past tense marker in OH but rather that of perfective aspect; the past tense marker was -a/-e. She argues that the OH tense system was a typical instance of 'complex tense systems' marking both external time and the internal temporal structure of situations, i.e., marking both tense and aspect. The similarity between the Old Hungarian and Latin tense systems is not a contact phenomenon, the result of some medieval Latinate influence; merely Old Hungarian and Latin select their means of expressing tense and aspect from the same set of limited possibilities determined by Universal Grammar. Finally, the authoress surveys the change that took place in the Middle Hungarian period with respect to the verbal morphosyntax of Hungarian. Whereas Old Hungarian marked viewpoint aspect morphologically, Modern Hungarian represents a language type in which the marking of situation aspect is grammaticalized. As a reflex of this change, the PredP projection, hosting the verbal particle, took over the role of aspect marking; the earlier aspect suffix was reinterpreted as a tense marker; and the OH tense marker was eliminated from the language.