Leopold III was King of Belgium for nearly two decades before and after World War II. He was a controversial monarch who ended his reign through abdication.

He was born on Nov. 3, 1901, in Brussels, the son of Prince Albert, the heir to the Belgian throne, and Elisabeth of Bavaria. Albert became king in 1909. Leopold grew up at court and made himself ready to succeed his father should the need arise.

Germany invaded Belgium in 1914, touching off the northern theatre of World War I. Albert took personal command of the Belgian troops, whose numbers were far fewer than the German invaders. Albert and his armies retreated farther and farther west, until they were behind the River Ypres, near the sea; there, they stayed for months and months. Leopold, who was 12 when the war began, won his father's permission to enlist and fought in the army. His military service was slight, however, because his father sent to him to the United Kingdom in 1915, to attend Eton College.

Leopold returned home after the war ended and set about helping his father rebuild the devastated landscape and repairing the people's moribund morale. Leopold married Princess Astrid of Sweden on Nov. 4, 1926. They had three children: Joséphine-Charlotte (1927), Baudouin (1930), and Albert (1934).

King Albert fell to his death while mountain climbing in the Ardennes on Feb. 17, 1934. Leopold then took the throne. He suffered further grief when he lost control of the car he was driving and ended up in a lake in Switzerland; Queen Astrid died in the crash.

Belgium had long professed neutrality and had tried to maintain that status during World War I. Germany ignored it in 1914 and ignored it again in 1940, when the blitzkrieg rained down on Belgian lands, beginning on May 10. As before, Belgium was outmanned and outgunned. The Belgian forces fought to keep their neutrality but, under the overwhelming weight of German attacks, surrendered, on May 27. (They had been effective enough early on to delay the German advance such that the British Expeditionary Force could complete the evacuation from Dunkirk.)

Prime Minister Hubert Pierlot and many of the rest of the Belgian government fled to Allied lands, setting up a government in exile. The occupying German army held Leopold prisoner. The king's surrender was by no means popular with the leaders of Allied countries, especially given what Leopold's father had done in the previous war. As well, many of the Belgian people struggling to make ends meet in the shadow of the German triumph expressed bitter disappointment in their monarch's actions. Leopold alienated even more people in late 1941 when he married again, this time to Lilian Baels, a wartime volunteer.

The king made several attempts to reconcile with the leaders of his government. He wrote a Political Testament, defending his actions and recommending various courses of actions once Belgium had been liberated. That event occurred in early 1945, by which time Leopold and Lilian had been moved to Germany. Allied forces rescued them in the closing days of the war, but they did not return home because resentment of his actions was still too high; instead, they spent six years in Switzerland, in exile. Leopold's brother, Prince Charles, served as regent during this time.

Many people in Belgium still resented Leopold for surrendering to Germany. A referendum in 1950 resulted in more than half of people saying that were in favor his returning. This sentiment was nowhere near being universal, however, and when he returned home, on July 22, 1950, he confronted a general strike, which turned violent and ended with deaths caused by soldiers firing into a crowd of protesters. A shocked Leopold agreed to grant his oldest son, then 20, regency powers. Even that act did not improve his standing with the Belgian people. Leopold abdicated on July 16, 1951, making Baudouin officially king.

Like his father, Leopold enjoyed the outdoors. He traveled extensively, collecting specimens of various animal species. He explored out-of-the-way places in South America.

Leopold III died on Sept. 25, 1983, in Brussels, after having emergency heart surgery. He was 81.