 Her father was Eduard Delius, part in a long line of entrepreneurs in the textile industry of the Westphalian city of Bielefeld while her mother was Christa Heinemann, a daughter of the former President.Through Christa, Rau is the niece of theologian Uta Ranke-Heinemann.She attended boarding school in Switzerland ("Hochalpines Institut Ftan") and the United Kingdom (Gordonstoun in Scotland, where Prince Andrew was a contemporary).