This article analyzes the changes in subject position in Portuguese between the sixteenth and nineteenth centuries in terms of the loss of verb-second grammar properties and the rise of an SVO grammar. Our analysis is based on the survey of an unprecedented amount of data for sixteenth-to nineteenth-century Portuguese in a syntactically annotated corpus. We argue that in Classical Portuguese (sixteenth to seventeenth centuries) the verb moves to C(omp), there is no preverbal position reserved for subjects, and all of the preverbal phrases are discourse-prominent constituents—which characterizes Classical Portuguese as a V2-type grammar. In Modern European Portuguese (from the eighteenth century on), in contrast, the verb does not move as high as C(omp), and there is a preverbal position reserved for subjects—in other words, this is an SVO grammar. We suggest that this change from a verb-movement, V2-type grammar to an SVO grammar derived from a prosodic change that happened in the seventeenth century, which also affected clitic placement.