The recently independent Greece chose Prince William of Denmark to be king, and as King George I of Greece he founded a royal dynasty that lasted for over a century.
The marriage of King Haakon VII and Queen Maud of Norway, the former Prince Carl of Denmark and Princess Maud of Great Britain, was the foundation of a new royal dynasty.
The marriage of King Frederick VIII of Denmark and Princess Louise of Sweden produced the future King Christian X of Denmark and King Haakon VII of Norway.
The marriage of King Christian IX of Denmark and Princess Louise of Hesse-Cassel began a dynasty that is still in power and their royal descendants rule throughout Europe
Defeating France in 1871 after unifying Germany enabled Otto von Bismarck to create the most militarily powerful nation in Europe, altering the prior balance of power.