Carl Gustaf Emil Mannerheim, Finnish general and politician, 6th President of Finland (d. 1951)
Baron Carl Gustaf Emil Mannerheim (Swedish pronunciation: [kɑːɭ ˈɡɵ̂sːtav ˈěːmɪl ˈmânːɛrˌhɛjm], Finland Swedish: [kɑːrl ˈɡʉstɑv ˈeːmil ˈmɑnːærˌhejm] (listen); 4 June 1867 – 27 January 1951) was a Finnish military leader and statesman. He served as the military leader of the Whites in the Finnish Civil War of 1918, as Regent of Finland (1918–1919), as commander-in-chief of Finland's defence forces during the period of World War II (1939–1945), as Marshal of Finland (1942–), and as the sixth president of Finland (1944–1946).

The Russian Empire dominated the Grand Duchy of Finland before 1917, and Mannerheim made a career in the Imperial Russian Army, rising by 1917 to the rank of lieutenant general. He had a prominent place in the ceremonies for Emperor Nicholas II's coronation in 1896 and later had several private meetings with the Tsar. After the Bolshevik revolution of November 1917 in Russia, Finland declared its independence (6 December 1917) – but soon became embroiled in the 1918 Finnish Civil War between the pro-Bolshevik "Reds" and the "Whites", who were the troops of the Senate of Finland, supported by troops of the German Empire. A Finnish delegation appointed Mannerheim as the military chief of the Whites in January 1918. Mannerheim was appointed as Commander-in-Chief of the country's armed forces in November 1939 after the Soviet invasion of Finland. He personally participated in the planning of Operation Barbarossa and led the Finnish Defence Forces in an invasion of the USSR alongside Nazi Germany known as the Continuation War (1941–1944). In 1944, when the prospect of Nazi Germany's defeat in World War II became clear, the Finnish Parliament appointed Mannerheim as President of Finland, and he oversaw peace-negotiations with the Soviet Union and the UK. He resigned from the presidency in 1946 and died in 1951.

Participants in a Finnish survey taken 53 years after his death voted Mannerheim the greatest Finn of all time. During his own lifetime he became, alongside Jean Sibelius, the best-known Finnish personage at home and abroad. Given the broad recognition in Finland and elsewhere of his unparalleled role in establishing and later preserving Finland's independence from the Soviet Union, Mannerheim has long been referred to as the father of modern Finland,

and the New York Times has called the Finnish capital Helsinki's Mannerheim Museum memorializing the leader's life and times "the closest thing there is to a [Finnish] national shrine". On the other hand, Mannerheim's personal reputation still strongly divides opinions among people even to this day, with critics highlighting his role as General of the White Guard in the fate of the Red Prisoners during and after the Finnish Civil War. Mannerheim is the only Finn to have held the rank of field marshal, an honorary rank bestowed upon especially distinguished generals.