This article argues that European vernaculars were in closer contact with one another and with languages spoken outside Europe in the 16th and 17th centuries than they had been in the Middle Ages, when Latin dominated written communication. Increased contact led to borrowing, mixing and hybridization, some of it highly self-conscious (as in the case of ‘macaronic’ poetry and drama). Mixing in turn led to a ‘purist’ reaction, first in the case of Latin and then in the case of vernaculars such as Italian, French, German, Dutch and even – to a lesser extent – English.