Eilat Gordin Levitan
It is true that Slobodka near Kovno is most well known in the Jewish
history for the Slobodka Yeshiva and the Musar movement, I think that
anyone would refer to it as it is in Kovno, Lithuania. ( I was there
and you could not clearly tell where Slobodka and Kovno are split)
There were other Slobodkas in the Vilna region. The Vilna region(
including the city of Vilna) was part of Poland between the wars. Now
much of that region is in Belarus. It is best to check the 1930 census
to see if they reported that they came >from Poland or Lithuania.
Sometimes it is wrong it is "Russia" which would be right only until
c 1920, but in most cases people knew by 1930 the political changes of
their country of birth.
Eilat Gordin levitan