And so the National Museum acquired its own building and before long it witnessed the advent of the new century. In 1913, in accordance with an anti-institutional act on the part of the Vienna government, the Provincial Diet and the Committee were dissolved and the museum found itself in dire financial straits, the threat even arising of its being closed for some time. Throughout the duration of the First World War the employees of the museum went to work from time to time only, especially in the winter months, when there was no fuel for heating the building. After the war the name of the museum was changed to the National Museum and up to the time of the Nazi occupation it was administered by a 12-member board, dissolved on 6 September, 1940. At the very end of the occupation the German air force dropped a bomb on the museum building, this having disastrous results for some of the collections.
Apart from the accumulation of items for the collections, filing activity and the protection and presentation of the exhibits, the programme of the National Museum now includes research and cultural-educational work. The Museum organizes exhibitions, arranges the presentation of specialized information to school youth and realizes lecture cycles and individual lectures, excursions, film projections, and open-house days for the pupils of basic and secondary schools, excursions to important natural localities in the Czech Socialist Republic for the children's Pioneer movement, the Union of Socialist Youth, students and apprentices.