Unexpected DNA matches on My Heritage

[Biggles50]

The sheer numbers of cM in the range does point towards a 3C or 2C1R level as having a reasonable probability.

Does any of the matches link to any of the other matches?

In my own tree I have linked to my own matches with the relationships I quote above.

Again using my own highest cM match I have a tree of 600 build around them and 12 other cM matches linked into the tree but as yet no link to me.

My Great Grandmother’s father was unknown, then I had a high cM match that linked to an Italian family and I found a high probability who my GGGF was.  I have over 100 likely Italian Cousins and of those with trees then a specific region is common to them all.

As I wrote in my first post, do have them undertake more DNA tests with others especially Ancestry.

[RWLL]

How many segments and how large are the segments shared with the 62.8cM match?

I do find at MyHeritage that for some of my relatives Scandinavian matches pop up sharing around 30cM, but they're over several segments of 6 to 8cM, which aren't very reliable.  But if the segments are larger and the SNP count is quite high then they could be meaningful matches.

The 62.8cM match shares 7 segments with my mum, the largest one being 21.2 cM. Some of the other top matches largest segments shared with her are 19.8cM, 30.8cM, 22.3cM, 26.5cM, 24.4cM. A couple of the other higher matches share many segments but only in the 7-10 cM range.

[RWLL]

One point also, on the historical side and that is what are the definitions of Scandinavian  and what is the definition of German you are using.  Germany as a country was founded in 1871. 

'The German Empire was founded on January 18, 1871, in the aftermath of three successful wars by the North German state of Prussia. Within a seven-year period Denmark, the Habsburg monarchy, and France were vanquished in short, decisive conflicts.'
http://www.rootschat.com/links/01rup/

I have Danish forebears and think, by their names, that as i get further back there will be ancestors from the current-day Germany in my tree. 
This is around the Schleswig-Holstein area. 
https://en.wikipedia.org/wiki/Denmark%E2%80%93Germany_border

Sweden did also control islands in the Baltic that may have changed to German? 

Anyway the point I am making is that when looking at heritage and genetic matches we need to have some knowledge of the history of the countries.  Of course this match may be the unknown gt grandfather  you are looking for.

I appreciate the response a lot! On my paternal side I have a German family who migrated to Sweden in the 1600s and have been doing some reading on that lately.

My mother's German family, however, came from Hessen, pretty much in the middle of Germany. None of these Scandinavian matches seem to share any of her German matches for common DNA. In fact, going through shared matches, I fail to see almost any matches to other European countries. There are plenty of North Americans amongst shared matches, but no German, British, Dutch matches.

[RWLL]

Given those substantial Cms and the volume  (" The top matches being 62.8 cM, 54.7 cM, 46.8 cM, 45.5 cM, 42.6 cM, etc"   )
I would say your mum has a Scandnavian ancestor,  and they are  not false matches.

My teen son has a known third great grandfather from Finland (  who was my mother in laws g grandfather). He was a sailor, met a local girl and the rest is history. ( they married, and he settled down in his new homeland in Wales, but many didn't of course)

My son's Scandnavian ( Finnish and Swedish matches mostly) substantial  matches  on My Heritage ( uploaded DNA).are in  the 20s and the high 30s -  36 , 37 ( for example  the highest match is 38cm with the largest segment being  24.3‎ cM )  - which is lower than your mum's matches  ( although my teen son is either one or two generations  below  your mother of course). 
So yes I'd guess your mum has a Scandinavian ancestor ,  given  those cms  compared to my  teenage son's matches  who 100% has a  Finnish  3 great grandfather.
 I'd  also take a  guess that the Scandinavian ancestor is not too far back  from your mother, maybe a second great.

Kind Regards

That's interesting to hear about a Finnish sailor in Wales! My mum's English family was living in Kent next to the Thames, which maybe gives me the hope that there was some Scandinavian sailor who visited those shores in my family's past.

My mum is most likely two generations back before your teen son's time, so that should explain her larger cM matches in comparison.

[RWLL]

The sheer numbers of cM in the range does point towards a 3C or 2C1R level as having a reasonable probability.

Does any of the matches link to any of the other matches?

In my own tree I have linked to my own matches with the relationships I quote above.

Again using my own highest cM match I have a tree of 600 build around them and 12 other cM matches linked into the tree but as yet no link to me.

My Great Grandmother’s father was unknown, then I had a high cM match that linked to an Italian family and I found a high probability who my GGGF was.  I have over 100 likely Italian Cousins and of those with trees then a specific region is common to them all.

As I wrote in my first post, do have them undertake more DNA tests with others especially Ancestry.

Thanks for both of your responses. I would love to have my mum take an Ancestry test, but she died a couple of years ago. She took a 23&me test in the past and that's what I was able to upload to My Heritage, solely in the hope to find some European matches for her.

Many of these Scandinavian relatives do match with each other in one way or another or they share common relatives between them. By looking at the shared DNA matches I'm starting to get an idea of what region(s) any potential ancestor(s) might have come from.