Need advice: unknown Spanish great-grandfather, no name, only DNA matches
In short: I have an unknown Spanish great-grandfather, no name, no photo, no documents, everyone who could have known anything is dead, and all I have are DNA matches. What would you do in this situation?
Long version:
I took a DNA test and got 14.4% Spanish. This didn’t really surprise me because there has always been a family story about a Spanish great-grandfather.
I’m Belarusian on my mother’s side, grew up in St. Petersburg, and know absolutely nothing about my father’s side.
My family is extremely secretive and half the information I have comes from random stories people told years ago.
The story is that my great-grandmother was married and worked as a drafting engineer. She traveled a lot for work around the USSR and sometime in the mid-1950s met a Spanish guy, supposedly in Leningrad. Family stories differ on who exactly he was - I’ve heard sailor, I’ve heard student. My grandfather was the result.
Another thing that made the family suspicious at the time was that my grandfather was dark-haired and brown-eyed while both of his legal parents were blond. Before anyone explains genetics to me, yes, I know that’s not how paternity works. I’m just repeating the family lore.
As far as I know, the Spanish guy eventually returned to Spain. Nobody in my family ever left the USSR, and my great-grandmother only spoke Russian.
One theory I had was that he might have been one of the Niños de Rusia, but without a name that’s pretty much a dead end.
Everyone who might have known the truth is dead, so DNA is basically all I have left.
I use MyHeritage. I ran AutoCluster, but I also have about 5% Finnish DNA and most of my matches are Finnish, so the clusters are kind of a mess because of Finnish endogamy.
My biggest Spanish matches are 160.3 cM and 121.9 cM, but they have no trees and don’t answer messages.
I also have quite a few Spanish matches with trees. I’ve tried looking at shared matches, copying trees, looking for common ancestors, etc., but I honestly feel like I’m stumbling around in the dark.
Is there a standard way people approach cases like this? What would be your next step?