Field marshal and statesman Gustaf Mannerheim (1867-1951) was the most acclaimed and the most hated Finn of the twentieth century. After three decades of loyal and distinguished service in the Russian Tsarist army, he returned to his homeland in 1917 to defend its new independence. This iconic figure led the Finnish forces as Commander-in-Chief during both World Wars, then ended his career as President of Finland. This new critical biography sets Mannerheim's entire life's work, and his often nerve-wracking decisions as a Finnish leader on the world stage, against the backdrop of his elite upbringing and lifestyle, his adventurous imperial career, his outspoken anti-communism, and his keen instincts for great power politics. Painful details emerge about Mannerheim's private life, and myths and rumours are scrutinised, as Henrik Meinander charts the complex legacy of this nationalist cosmopolitan who found himself fighting on the same side as Hitler. Meinander paints his portrait with strong contrasts and bright colours. This is the story of a multicultural Russian empire, a newborn nation-state treading warily between Europe's military titans, a front of the Second World War not easily reduced to moral binaries--and, above all, a shrewd political operator playing many a dangerous game.