Admiral is the story of Admiral Aleksandr Kolchak, and his fight against the Bolsheviks during the Russian Revolution.
From Wikipedia:
Alexander Vasilyevich Kolchak CB (Russian: Алекса́ндр Васи́льевич Колча́к, 16 November [O.S. 4 November] 1874 – 7 February 1920) was a polar explorer and commander in the Imperial Russian Navy, who fought in the Russo-Japanese War and the First World War. During the Russian Civil War, he established an anti-communist government in Siberia—later the Provisional All-Russian Government—and was recognised as the “Supreme Ruler and Commander-in-Chief of All Russian Land and Sea Forces” by the other leaders of the White movement from 1918 to 1920.[1] His government was based in Omsk, in southwestern Siberia.
For a year and a half, Kolchak was the internationally recognised leader of Russia. However, his effort to unite the anti-Bolshevik elements mostly failed; Kolchak refused to consider autonomy for ethnic minorities and refused to cooperate with non-Bolshevik leftists, and also heavily relied on outside aid. As his White forces fell apart, he was betrayed and captured by independent units who handed him over to local Bolsheviks, who executed him