On 5 September 1951, Ernest Augustus married Princess Ortrud of Schleswig-Holstein-Sonderburg-Glücksburg (1925–1980). The wedding was attended by many important royal figures, including his sister Queen Frederica and her husband King Paul of Greece, and the heads of the houses of Saxony, Hesse, Mecklenburg, Oldenburg, and Baden. The wedding was followed with a reception in the Gallery Building at Herrenhausen Gardens, the only part of the House of Hanover's former summer palace still intact, as the palace itself had been burned down during World War II.