After the death of Archduke Joseph in 1847, his children inherited the Üröm state, who even survived both World Wars. The chapel was sacked, the valuables taken away and the coffins were open, but the remains weren't profaned, so the clothing and jewelry remained intact. In 1945, due to the Collectivization in Hungary near the property some farmers were established until 1953, when in the Russian Orthodox Church took over the ownership of the site. In November 1977 the National Institute of Forensic Medicine, the National Institute of Chemistry of Justice and the Budapest History Museum archaeologist and anthropologist experts carried out detailed investigations in the Üröm Mausoleum.