[Ger-Poland-Volhynia] British sounding surnames in current Poland

[Vera Miller]

Hello all,
I have two direct ancestors who have surnames that sound British. I am trying to understand this. I was part of the beta group for Ancestry.com's newest DNA test that determines ethnicity. I am Russian/Finish and Eastern European.
How do I explain that my 5th-great-grandmother was Anna Elizabeth Engler (born 06 Nov 1768 in Schwiebus) and her father's first name was Hans, definitely not a British given name. And then a 6th-great-grandmother was Katherine Elizabeth Marsch. I do not have a birthdate or birthplace. She lived in Züllichau (now Sulechow, Poland).
VeraBlog-https://lostrussianfamily.wordpress.com/