Christian IX (8 April 1818 – 29 January 1906) was King of Denmark from 1863 to 1906. From 1863 to 1864, he was concurrently Duke of Schleswig, Holstein and Lauenburg. Christian married his second cousin, Princess Louise of Hesse-Kassel, in 1842. Their six children married into other royal families across Europe, earning him the sobriquet "the father-in-law of Europe". Most current European monarchs are descended from him, including Queen Margrethe II of Denmark, Queen Elizabeth II of the United Kingdom, King Philippe of Belgium, King Harald V of Norway, King Felipe VI of Spain, and Grand Duke Henri of Luxembourg. The British consort Prince Philip, Duke of Edinburgh is also an agnatic descendant of Christian IX, as is Constantine II, the former and last King of the Hellenes.