This opulence could not be sustained indefinitely, and the Wall Street Crash badly damaged the family finances, decreasing their interest in, and visits to, Rùm. Sir George died in France, in July 1939, shortly before the outbreak of World War II, and was interred in the family mausoleum on Rùm. His widow continued to visit Rùm as late as 1954. When in 1957 Lady Bullough sold the whole island, including the Castle and its contents, to the Nature Conservancy Council, on the understanding that it would be used as a national nature reserve, the mausoleum was the only part of Rùm not included in the sale. Lady Bullough died in London, in 1967, at the age of 98; she was buried next to her husband in the Rùm mausoleum.