IX. King Keresztely of Denmark, who reigned from 1863 to 1906, was a significant figure in the history of Europe. He was born on April 8, 1818 in Schleswig and died on January 29, 1906 in Copenhagen, in the Amalienborg Palace. He married his second cousin, Princess Lujza of Hesse-Kassel, on May 26, 1842. During his lifetime, he became known as the "father-in-law of Europe" as his six children married into various European royal houses. Among his children was VIII. King Frederick of Denmark, Queen Alexandra of Britain, King George I of Greece, Tsarina Maria Fyodorovna of Russia, Princess Tira of Denmark, and Prince Valdemar of Denmark. Most of today's European rulers are IX. Descendant of Keresztely. During his reign, Denmark underwent significant changes, including the Danish-German War of 1864, which resulted in significant territorial losses for the Danish crown. This war left a deep mark on the Danish national consciousness and the authority of the royal family. After the war, Denmark adopted a new constitution, which came into force in 1866, which modernized the Danish parliamentary system. IX. During the reign of Christian, Denmark gradually transformed into a modern state, which moved towards parliamentarism and democratic institutions. IX. Keresztely's memory is preserved in Roskilde Cathedral, where he was laid to rest. Through his reign and family connections, he shaped the history of Europe's royal families, and his legacy can still be felt in the political and cultural life of the continent.

IX. Keresztély ascended the throne in 1863 and immediately began to prepare for the Danish-German war, which took place for the possession of the duchies of Schleswig-Holstein. In the war, Denmark was defeated and lost the duchies. As a result, he had to face a decrease in the value of the Danish crown. After the war, IX. He introduced Christian reforms in the Danish coinage. In 1864, he introduced the new Danish krone, which was more valuable than the previous one. In addition, new coins and banknotes were issued.IX. During the reign of Christian, the modernization of the Danish coinage also began. In 1865, a new mint was built in Copenhagen, which used modern technologies.IX. During the Christian era, Danish coinage underwent significant development. Increasing the value of the Danish krone and modernizing the coinage contributed to the stabilization of the Danish economy.