Foreigners

Linguistic curiosity: An old Proto-Germanic word walkiskh*  was used for all foreigners, which, in their world, were 99% Celts. It was an insulting term, which meant also slave, servile, not-very-art-smay, if you catch my drift. Just about what every tribe in the history of mankind thinks of other tribes.

Because it was applied so universally, it was the name various Teutons and Saxons gave to a lot of people, including the Welsh, the Walloons (Beligium), the Vlachs (Romania), the Cornish (Cornwall), and even walnuts, which were not a normal English hazelnut, but some damn suspicious foreign nut.

Derivatively, the surnames Wallace, Walsh, Welch as well

*approximate. always.  these languages were always highly variable affairs.