"Named" is a bit ambiguous: given name ("first name", "Christian name") or surname ("last name")?

I have good sources for English. Reaney and Wilson, A Dictionary of English Surnames, dates Euerdai de Flandria 1191, Eustache de Lorreyne 1333 (from Scotland), Robert Normandie 1369 and John Normand 1216 and John le Norman 1221. They say that all those are from the corresponding geographical areas, or for "Norman" it's an adjectival form "one who is a ___" or the more literal meaning "north man" (there are a lot of names starting North). NOTE: they admit in the third edition intro, "Similarly the etymologies suggested are usually my own, and from the nature of the surnames included tend to be either obvious or highly speculative", so have grains of salt handy. Walter Burgoin 1086 they derive from "the man from Burgundy", French "Bourgogne". William le Gascun 1208 is pretty clearly from Gascony. Richard de Espaigne 1177 et seq. may be from Espinay in Brittany, {E'}paignes in France, or "Later, the name probably derives from Spain, especially in the case of London merchants". Germanus was a given name in Domesday Boke in 1086, so it could be from the given name, but Gilbert le German 1318 is pretty clearly descriptive / locative.

As other counter-examples, I don't find a form of Bohemia or Moravia (an earlier name), Austria, Russia, Italy, Genoa, Venice, or Naples. There can be a problem with "false friends". For example, there's Jordan de Saxton 1208, but there's a town of Saxton in Yorkshire. Norway can apparently be a modern form of Northway, in the Moors, and Norway in Devon. Forget Pole -- too many famous false friends -- and Romanus was the name of two martyrs and started as a given name in England.

I'm not "you can rip my arm off if I'm wrong" certain, but I surmise that locative surnames can be found in Britain when a significant number of people came to Britain from those places, and places on a nearby coast are likelier to have significant trade links and travel than inland Europe like Bohemia (though, for example, English aethelings ended up in Hungary at one point).

I don't have examples of any of these being used as given names, except that Norman was a given name in England even before the Norman Conquest (presumably from "north man", for for Scandinavians). Surnames started being used as given names in the 1500s (Guildford Dudley being the famous example), so they may have migrated to given name positions then, except that Norman survived in Scotland as a given name after it died off in England as a given name in the 14th C (per E. G. Withycombe, The Oxford Dictionary of English Christian Names).