even if your grandpa was born in Austria-Hungaria, its possible he might have spoken romanian. Austria-Hungaria covered very large area, much larger than todays Austria and Hungary. It included also Slovakia, Czech republic, parts of Romania, Croatia, Ukraine etc. Even today, there are some areas near romanian border where people still speak romanian. I would guess its mostly old inhabitants of the area, but i dont know. im from Slovakia and in the place where I live lot of people still speak or understand hungarian, because its so close to the border. In fact the place my grandpa was worn, which is now in Slovakia was Hungary then.