 The Crimean War (1853–1856), a conflict fought between the Russian Empire and an alliance of the French Empire, the British Empire, the Ottoman Empire, the Kingdom of Sardinia, and the Duchy of Nassau, was part of a long-running contest between the major European powers for influence over territories of the declining Ottoman Empire.Russia and the Ottoman Empire went to war in October 1853 over Russia's rights to protect Orthodox Christians; to stop Russia's conquests France and Britain entered in March 1854.While some of the war was fought elsewhere, the principal engagements were in Crimea.