This chapter provides a detailed presentation of the main data and arguments which have been proposed in favour of claiming that the Medieval Romance languages were V2 systems and considers data from Old French, Old Occitan, Old Italo-Romance varieties, Old Spanish, and Old Portuguese. It provides new qualitative and quantitative evidence to show the nature of the prefield, Germanic inversion, matrix/embedded asymmetries, and the precise types of verb-first and verb-third-or-greater orders provide new evidence in favour of the V2 hypothesis. It also suggests that the diachronic emergence of a V2 grammar is entirely plausible on the basis of the available data. The main objections to the V2 account proposed in the literature are evaluated and argued to face empirical and theoretical problems.