It is widely accepted that the Viking presence in 10th-century Rouen area (future duchy of Normandy) left no discernible linguistic traces in the langue d’oïl language group beyond some scattered words relating to shipping and other very specific operations. However, as I was musing on the biography of the French word “seuil”, I noticed the striking similarity between the fr. seuil and the eng. sill. There was a double opportunity for this exercise. The first was provided by Gérard Genette’s book “Seuils” famously published at the “Editions du seuil”, the other by the seminar I’m teaching on the viking incursions in Neustria in the 9th century. Having dug a bit deeper, I saw that sill was quite old, actually dating back to the Old English word syll (alt. sp. sylle) which shares the root with other old Germanic languages. The first recorded occurrence of the fr. seuil was ca 1170 in the Anglo-Norman text “Quatre livres des rois”, an epitome of the four books of Kings in the Old Testament:
“De rechief al demain truvèrent Dagon à terre, gisant devant l’arche, e les puinz e les chief colpez li furent sur le suil” (I, V, §4).
It could very well have been that suil was one of the many Old English imports into Norman French after the Conquest. Yet there is a possibility, and it can’t be easily dismissed, that suil was already there in oïl when the Anglo-Norman connection came about. A further argument has to do with spelling. The Old Norse for sill is svill, which may explain the scribal u/v in the French suil.
Thus, the earliest presence of suil in Anglo-Norman may not be an accident of written sources survival but an instance of a Scandinavian word subsisting in a language that evolved in an erstwhile Norse linguistic territory.