Christian IX was King of Denmark from 1863-1906 and Queen Louise from 1863-1898. They were called the Grand Parents of European royalties, their Grand Children became rulers in Great Britain, Greece, Norway and Denmark.
He was the first King in the new Royal family of the House of Schleswig-Holstein-Sonderburg-Glücksburg after King Frederik VII had no children and the end of the House of Oldenburg.