The aim of the paper is to analyse the sociopragmatic evolution of the nominal treatments don and señor in primitive Iberoromance (10th–13th centuries). Through the search in the notarial documents of that period, extracted from CORDE, the author examines how the insertion of the new nominal treatment SENIORE, inexistent in classical Latin, spreads sociopragmatically causing the pragmatic corrosion of the initial treatment from DOMINUS.