Charles Michael, Duke of Mecklenburg (German: Carl Michael Herzog zu Mecklenburg; (Russian: Михаил Георгиевич; 17 June [O.S. 5 June] 1863 – 6 December 1934) was an officer in the Imperial Russian Army, heir presumptive to the throne of Mecklenburg-Strelitz and from 1918 head of the Grand Ducal House.

He was born in Oranienbaum, Russia, a grandson of Grand Duke Georg of Mecklenburg-Strelitz via his second son Duke Georg August of Mecklenburg (1824–1876) and his wife Grand Duchess Catherine Mikhailovna of Russia, a granddaughter of Emperor Paul I of Russia. Charles Michael studied at the University of Strasbourg and gained a PhD. As he was born into the Russian branch of the Grand Ducal house of Mecklenburg-Strelitz, Charles Michael and his older brother Duke George Alexander, both served in the Russian Imperial Army with Charles Michael achieving the rank of Lieutenant General. When his brother died in 1909 Charles Michael was appointed the guardian of his children Katharina, Marie, Natalia and Georg by Adolf Friedrich V. From 1908 to 1910, he served as the head of artillery in the 1st Army Corps of the Russian Imperial Army.

On 24 June 1914 two weeks after the death of his cousin Grand Duke Adolf Friedrich V, Charles Michael wrote to the new Grand Duke Adolf Friedrich VI informing him that he wished to renounce his rights to the throne of Mecklenburg-Strelitz. On 7 August shortly after the outbreak of World War I he became a naturalised Russian citizen.

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