Yes! It was always small. Probably larger in comparison to other towns in the past. I am not sure.

By the way Poland (Bialystok and Warsaw) archives may have some records. Such as this one in Bialystok – list of those who paid taxes. http://baza.archiwa.gov.pl/sezam/ela.php?l=pl&mode=showspis&id=9946

Your relatives living in Belarus since 1939 will definitely have many records in Grodno state archive.