Complex sentence: In 1944, the Museum of Natural History of Slovenia (then known as the Museum of Natural Sciences) became independent despite being located in the same building and in 1946 the majority of its archives to the Archives of the Republic of Slovenia.
Split into simpler sentences: In 1944, the Slovenian Museum of Natural History (then known as the Museum of Natural Sciences) became independent despite being located in the same building. In 1946 the majority of archives has been removed to the Archives of the Republic of Slovenia.