Leopold III may refer to:
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Leopold III, Margrave of Austria (1073–1136), sixth Margrave of Austria
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Leopold III, Duke of Austria (1351–1386), co-Archduke of Austria and co-Duke of Styria
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Leopold III, Duke of Anhalt-Dessau (1740–1817), first Duke of Anhalt-Dessau
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Leopold III, Prince of Lippe (1821–1875)
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Leopold III of Belgium
Leopold III (3 November 1901 – 25 September 1983) was King of the Belgians from 23 February 1934 until his abdication on 16 July 1951. At the outbreak of World War II, Leopold tried to maintain Belgian neutrality, but after the German invasi ...
(1901–1983), fourth King of the Belgians
{{hndis, Leopold III