And I suggest little less confidence.
Olaf do not exaggerate. I have found, of course your murzać. It's enough to google it.
But contrary to you, I'm not convinced. Yes, there is a few links, but all they look like they are going from one source (you maybe know the theory of mems' diffusion). Unfortunately in most cases, when authors link
Murzyn with
murzać, they're doing it to underline how derogatory is this word for example guys from the portal: afryka.org.
I'd prefer to believe to what well known authorities in linguistics have to say.
Aleksander Brückner, the greatest Polish etymologist wrote:
common -in (as in Rusin) singularis added to German Mohr from Latin maurus, 'black'. and asked if
murzyć isn't from
murzyn.
Samuel Bogumił Linde, the author of first modern Polish dictionary in 1809 wrote:
MURZYN - in Czech mouřenin, èernoch, Slovak mauřenin, Serbian mor, Russian - муринЪ [murin].. from Latin maurus, der Mohr - Nigryczykowie abo murzyny, nazwisko które daiemy narodom czarnym; powszechnie tak nazywamy ludzi czarnych, z kraiów południowych pochodzących (English translation: Nigerians or murzyny, name given by us to black nations;we usually call in such way black people from southern countries) and he presented additional meaning = German
ein Mohrenkopf i.e. a horse with black head.
Encyklopedia PWN, Polish main Encyclopaedia:
from Latin Mauri (Moors).
encyklopedia.pwn.pl/haslo.php?id=3944532