on August 9th, 2020.
Jacob Rothschild describes the 19th Century policy of keeping money in the family by inbreeding. James Mayer de Rothschild even married his own niece Betty Rothschild, the daughter of his elder brother Salomon Mayer von Rothschild.
Source:
Youtube: Waddesdon Manor
Lord Rothschild presentation 8 Nov 2018 Sothebys NYC
https://www.youtube.com/watch?v=hhaihcUNAnE