Christian X died in 1947 and was succeeded by his eldest son, Frederik IX, who in 1935 had married the Swedish Princess Ingrid.
The marriage produced three daughters, Margrethe, Benedikte (b.1944), who in 1968 married Prince Richard zu Sayn-Wittgenstein-Berleburg, and Anne-Marie (b.1946), who in 1964 married Constantine II, then King of the Hellenes.
Unlike his father, Frederik IX from the start accepted that the king has no real political power. With his family, he instead modernised the monarchy, adapting it to the representative government and its democratic ways. By virtue of his bluff, informal manner and obvious joy in his family, Frederik IX became the exponent of post-war popular values without jeopardising the dignity and distance inherent in the nature of monarchy.
His eldest daughter, Margrethe II, has managed to continue and develop this line, so that the royal house and the monarchy today are more popular than ever. The deaths of Frederik IX in 1972 and Queen Ingrid in 2000 therefore caused genuine national mourning.