My great-grandfather immigrated from Greece in 1903. We have been able to find a number of American documents about him, but none of them have information about his parents.
In English, he spelled his name Speros Brineas. We have his Declaration of Intention, his Preliminary From for Petition for Naturalization, his WWI Draft registration, the ship manifest, some correspondence, etc.
On these, he writes that he was born in Korentho, which I assume is the same as Corinth, and his birthdate as 12/12/1876. On his petition for naturalization, he writes that his mother's maiden name was Pearl Brineas (I wish the form asked for father's name!).
My first question is fairly specific - is Brineas a common enough name that it's likely that it really is his mother's maiden name, or should I assume that he made an error, and put her married name instead of her maiden name?
My second question is much more general - what is the best way to proceed from here? I feel like we have exhausted the documentation trail in the US without finding the needed information, and that we probably need to get some information from Greece.