Counts of Celje
The settlement was first mentioned in a document written on 31 October 1197 in Strasbourg. It mentions two noblemen from Boštanj, who were subjects of the Diocese of Krško. The second mention dates to 1228 and stats that there were ten farms in Boštanj at the time. Since 1322, Boštanj was property of the Lords of Žovnek and later of the Counts of Celje, who succeeded them.