Boseň is a municipality and village in Mladá Boleslav District in the Central Bohemian Region of the Czech Republic. It has about 500 inhabitant…Boseň is a municipality and village in Mladá Boleslav District in the Central Bohemian Region of the Czech Republic. It has about 500 inhabitants. The villages and hamlets of Mužský, Zápudov and Zásadka are administrative parts of Boseň.