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.Growing up as a prince of Schleswig-Holstein-Sonderburg-Glücksburg, a junior branch of the House of Oldenburg which had ruled Denmark since 1448, Christian was originally not in the immediate line of succession to the Danish throne.