Soil erosion induced by rainfall stands out as a prominent concern within contemporary natural phenomena. A retrospective analysis is required to better understand the behavior of the erosion process within a territory. However, the lack of an adequate local database of precipitations can be considered one of the main limitations to be able to approach this type of work. The objective of this investigation is to analyze the spatio-temporal distribution of the RUSLE R-Factor from 1901 to 2020 using satellite raster information and local approaches. The methodology entailed delineating hydrographic basins based on regional literature sources; the use of GPCC precipitation databases at pixel scale and; calculating rainfall erosivity using a national methodology. The results showed a high spatial variability of the R-Factor among the Ecuadorian basins, but a low variability over every twenty years up to the year 2000. Rainfall erosivity was identified as a crucial element to identify more precisely the trends over the years in relation to rainfall.