Princess Marie Luise Alexandra Karoline of Hohenzollern-Sigmaringen (17 November 1845 – 26 November 1912), later Countess of Flanders, was a princess of Hohenzollern-Sigmaringen, later simply of Hohenzollern. She married Prince Philippe, Count of Flanders, second son of King Leopold I of Belgium, and she was the mother of King Albert I.
Albert I (8 April 1875 – 17 February 1934) was King of the Belgians from 23 December 1909 until his death in 1934. He is popularly referred to as the Knight King (Dutch: Koning-Ridder, French: Roi-Chevalier) or Soldier King (Dutch: Koning-Soldaat, French: Roi-Soldat) in Belgium in reference to his role during World War I.
Albert was born in Brussels as the fifth child and second son of Prince Philippe, Count of Flanders, and Princess Marie of Hohenzollern-Sigmaringen, Albert succeeded his uncle Leopold II to the Belgian throne in 1909. He married Elisabeth of Bavaria, with whom he had three children.