I’ve been conducting genealogical research and wanted to investigate a change of vowel in our surname. My surname is ‘- - - - yra’, with that (paternal) side of the family coming from Katowice (Kattowitz).
To us, they were Polish but, as we know, history is complicated and unforgiving; looking at it more thoroughly they were very much German/Polish (Poland didn’t exist for years/the city was part of the German empire, which complicates it all, and they had a mixed parental heritage) but understandably ditched that side of their identity on emigration to the UK post-WWII.
I found out from church records/Kirchenbuch that my great grandfather (b.1883) had the name - - - - ÿra, and was wondering about the use of this character in an old Silesian context in German-Poles, and if it has any significance or interesting indication.
Even weirder, his father (b.1854) and before went by - y - - era, in contrast to my - e - - yra, with no umlautend sound and no other (consonant) changes.
Seems like certain vowels and sounds were quite interchangeable in this ‘borderland’ region?
I do not speak the Polish language. So take my experience only as one from the German perspective please.
The glyph used to represent a letter does not really tell us all about the sound/pronunciation of a vowel, by itself.
The two dots are called "Trema" and usually indicate that a vowel is pronounced different. Not in this case: The letter ÿ in old German cursive scripts (called Kurrent) is different. Here it was simply a combination of -ij which was used for words that end with a "long i". In Kurrent handwriting ij is indistinguishable from ÿ so there was no differentiation.
"ÿ" in German Kurrent script was the correct way how everyone wrote the letter y from the 16th until the early 20th century. This was helpful to distinguish the letters better, because Kurrent tends to look like zig-zag without diacritical signs. On a similar note, we wrote the letter u like ů. Some people still today write u like ū for this reason.
Two letters merging into a single letter was typical for German Kurrent (called "Ligatur"). This happened with ch, ck, ff, fi, fl, ſz, ll, sch, si, ss, st, tt, tz, st. Most famously is probably ſz (sz) which became ß.
There is not much more to say about this, I believe: y was ÿ. As an example, do have a look at this letter by Goethe dated at the end with "am 9 Maÿ 1802".
The Trema that are currently used in German ä, ö, ü are different. They developed from a simplification of aͤ, oͤ, uͤ (=ae, oe, ue) and do indeed indicate a different pronunciation.
As a sidenote:
