Oskar-Ferdinand Kazimirovich Grippenberg (Swedish: Oskar Ferdinand Casimir Gripenberg, Russian: Оскар Казимирович Гриппенберг) (1838-1915) was a Russian military leader from the Grand Duchy of Finland. He was commanding general of the Russian Second Manchurian Army during the Russo-Japanese War.
Oskar-Ferdinand Grippenberg was born on 13 January 1838 in Ikaalinen (Swedish: Ikalis), Finland, the son of Uddo Sten Casimir Gripenberg and Maria Wilhelmina Elisabeth Ladau. The family were Swedish-speaking Finns and his father untitled nobility. Oskar-Ferdinand Grippenberg married Hedvig Ida Angelique Lundh in 1874. They had four children.
Grippenberg began his military career in 1854. His first experience of battle came in the Crimean War. He took part in many later wars, steadily climbing up the ranks. For his actions in the Turkestan War 1867-1868 Grippenberg received the highly prestigious Cross of St. George of the fourth degree, the Golden Saber and promotion to Lieutenant Colonel. For his actions in the Russo-Turkish War of 1877-1878 Grippenberg received the Cross of St. George of the third degree in 1877. This was an unusual distinction as he was a Colonel at the time and the third degree was normally only awarded to officers of at least general's rank. He was however promoted to Major General on 22 February 1878. In 1890 he became commander of the prestigious First Division of the elite Life-Guards. He lost this position in 1898 after criticizing heavy-handed Russian actions in Finland. He was eventually reassigned to command the 6th Army Corps in 1900, and in 1904 was honored with the title Adjutant General to the Tsar.
General Grippenberg was assigned to command the 2nd Manchurian Army when the Russo-Japanese War broke out in 1904. Grippenberg perceived a weakness in the Japanese lines and in January 1905 launched a surprise assault that threw the enemy's left flank into disarray. The Battle of Sandepu was Grippenberg's most famous engagement, but victory was denied by the cautious nature of the commander-in-chief General Aleksey Kuropatkin. Kuropatkin refused to support the action and soon ordered a halt to the offensive. Relations between the two officers had been strained from the beginning and Grippenberg asked to be relieved of his command of the 2nd Manchurian Army on 29 January 1905, only a day after the battle ended. Tsar Nicholas II allowed Grippenberg to return to Saint Petersburg immediately, although he was not formally relieved until March. Grippenberg blamed Kuropatkin for Russia's defeat in the war, which sparked a war of words between the two men.
Grippenberg's star continued to rise despite his controversial resignation. The Tsar still thought highly of Grippenberg and on 30 April 1905 appointed him to the State Council of Imperial Russia. Grippenberg was also appointed Inspector General for the Infantry on 28 June 1905, but did not hold the position for long as he resigned from the army on 16 January 1906. He remained a State Councillor and General Adjutant.