There are some historical, biblical and fictional figures and others who are referred to by anglicized forms of their names. Always worth a quick check. After all, the same happens in Dutch – Lodewijk XIV, Karel de Grote, Winnie de Poeh, Zweinstein…
So yes, there are quite a lot of anglicizations to be aware of.
- Biblical, saints, popes, e.g. Maria-Mary, Maria Magdalena-Mary Magdalene, Paulus-Paul, Pontius Pilatus-Pontius Pilate
- early scientists and similar, e.g. Snellius => Snell’s Law of Refraction
- historical figures and royalty, especially older, e.g. Lodewijk XIV-Louis XIV, Karel de Grote-Charlemagne, Willem de Zwijger-William the Silent
- and from Antiquity, e.g. Virgilius-Virgil, Aristoteles-Aristotle, Marcus Antonius-Mark Antony, Homerus-Homer, Trajanus-Trajan
- and the three planets with names derived from their deities: Mercurius-Mercury, Saturnus-Saturn, Neptunus-Neptune
- children’s fictional characters, e.g. Knorretje-Piglet, Zweinstein-Hogwarts, Idefix-Dogmatix, Nijntje-Miffy
And don’t think it’s entirely a thing of the past. Dutch people abroad with names that could confuse the locals sometimes simplify the spelling. Mondriaan-Mondrian, Cruijff-Cruyff, Van Nistelrooij-Van Nistelrooy.
Prevalence: moderate. Higher than you might have expected. Less so for the fictional ones and the obvious historical names, but surprisingly common when other such names are in the text.
Frequency: high. Often multiple times in the same text.
Native: no. Not if we know what we’re talking about.