Why did Britain fight the Crimean War?

The Crimean War gave us war photography, modern nursing, the Thin Red Line and the charge of the Light Brigade, but they were not the reasons why British troops fought some 1,600 miles from home. Fearing that Russian expansion in the Turkish controlled Danube region (modern-day Romania) would eventually continue into British India through Afghanistan, Britain allied with the declining Ottoman empire – the ‘sick man of Europe’, as it became known – France and Piedmont-Sardinia.

Religion was a key factor in France’s involvement in the war. It claimed sovereign authority over Roman Catholics in the Ottoman empire, who had long disagreed with the Orthodox Christians, deemed under Russian protection, over access to holy sites. Britain and France declared war against Russia in March 1854, hoping to swiftly take the port city of Sevastopol and destroy Russian naval power in the Black Sea. Instead they would endure an 11-month siege.