Stephenson:Neal:Quicksilver:847:Belgian river-boats (St.CountZero)

From the Quicksilver Metaweb.

Eliza is indeed travelling in what is now the kingdom of Belgium. The general area has been known by variations on that name since the Romans (see De Bello Gallico: "Gallia est omnis divisa in partes tres, quarum unam incolunt Belgae..."). However, the actual independent kingdom was only formed in 1831: I doubt the river-boats would have been referred to by anybody as "Belgian". Locals would most likely have used a regional term, as they probably didn't think of themselves as Belgians.