Dear Jadran, please read WP:RS first. We need reliable sources, not original researchand  subjective feelings. About country and administrative regions - Czechoslovakia was divided to regions (kraje) (see Administrative divisions of Czechoslovakia) and one was Severomoravský kraj (Region of the North Moravia), but this region include whole Czech Silesia. With your logic Czech Silesia was united with Moravia and now is "deleted" from maps. Of course, today is this commies mistake repaired and exist Moravian-Silesian Region. Again, don't mix Lower Silesia and Province of Lower Silesia.