Jan Paweł II – Was only ever Polish/Slavic pope

Sorry for interupt, just to mention another pope of Slavic origin, pope Sixtus V, his father was from modern-day Montenegro, of Šišić or Svilanović family.

During his pontificate "the church of Saint Jerome in Rome was rebuilt to be used specifically for the people who spoke the Illyrian (ie. South Slavic) language. He also established a college of eleven Slavonic clerics…"