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.

Albert grew up in the Palace of the Count of Flanders, initially as third in the line of succession to the Belgian throne as his reigning uncle Leopold II's son had already died.

In his youth, Albert was seriously concerned with the situation of the working classes in Belgium, and personally travelled around working-class districts incognito, to observe the living conditions of the people.

[1] Shortly before his accession to the throne in 1909, Albert undertook an extensive tour of the Belgian Congo, which had been annexed by Belgium in 1908, finding the country in poor condition.

[2] Albert was married in Munich on 2 October 1900 to Bavarian Duchess Elisabeth Gabrielle Valérie Marie, a Wittelsbach princess whom he had met at a family funeral.

A daughter of Bavarian Duke Karl-Theodor, and his second wife, the Infanta Maria Josepha of Portugal, she was born at Possenhofen Castle, Bavaria, Germany, on 25 July 1876, and died on 23 November 1965.

For instance, when his former tutor General De Grunne, in his old age, entered the Benedictine monastery of Maredsous in Belgium, King Albert wrote a letter to him in which he spoke of the joy of giving oneself to God.

"[8] To another friend, Lu Zhengxiang, a former prime minister of China who became a Catholic monk in Belgium, Albert wrote: "Consecrating oneself wholly to the service of Our Lord gives, to those touched by grace, the peace of soul which is the supreme happiness here below.

"[4] In an interesting meditation on what he viewed as the harm that would result if Christian ideals were abandoned in Belgium, he said: "Every time society has distanced itself from the Gospel, which preached humility, fraternity, and peace, the people have been unhappy, because the pagan civilisation of ancient Rome, which they wanted to replace it with, is based only on pride and the abuse of force" (Commemorative speech for the war dead of the Battle of the Yser, given by Dom Marie-Albert, Abbot of Orval Abbey, Belgium, in 1936).

The King, fearing the destructive results of the war for Belgium and Europe and appalled by the huge casualty rates, worked through secret diplomatic channels for a negotiated peace between Germany and the Entente based on the "no victors, no vanquished" concept.

From 23 September to 13 November 1919, King Albert, Queen Elisabeth of Bavaria, and their son Prince Leopold made an official visit to the United States.

[7] The Allies considered Belgium to be the chief victim of the war, and it aroused enormous popular sympathy, but the King's advice played a small role in Paris.

In 1920 Albert changed the family name from "Saxe-Coburg-Gotha" to "House of Belgium" (van België, in Dutch; de Belgique in French) as a result of strong anti-German sentiment.

[23] A passionate alpinist, King Albert I died in a mountaineering accident on 17 February 1934, while climbing alone on the Roche du Vieux Bon Dieu at Marche-les-Dames, in the Ardennes region of Belgium near Namur.

There are two possible explanations for his death, according to the official juridical investigations: the first was that the king leaned against a boulder at the top of the mountain that became dislodged; the second that the pinnacle to which his rope was belayed broke, causing him to fall about 60 feet (18 metres).

[27] In 2016, DNA testing by geneticist Dr. Maarten Larmuseau and colleagues from the Katholieke Universiteit Leuven on bloodstained leaves that were collected in 1934 from Marche-les-Dames concluded that King Albert had died at that location.