In this paper we deal with constructions that contain the so-called aspectual se in Spanish in order to determine whether the properties associated with these constructions are reflected in historical data of American Spanish. Taking as a starting point the observations of De Benito (2021) on data from peninsular Spanish from the COSER corpus, we show that the theoretical-practical difficulties in the study of this phenomenon are not exclusive to current Spanish nor to peninsular Spanish, but are evident in data from American Spanish from a diachronic perspective. By collecting data from the CORDIAM corpus, we illustrate instances of aspectual se in the Spanish of the Río de La Plata (Argentina and Uruguay) from the 16th-19th centuries. We conclude that the most widespread analyses are based on a series of strict contrasts and (a)grammaticality tests that are not necessarily reflected i...