When Russia invaded the Turkish Balkans in 1853, fears of Russian dominance in the Mediterranean and Middle East led Britain and France to invade the Crimean Peninsula to destroy Russian naval capabilities. The ensuing Crimean War (1854–56), which involved new techniques of modern warfare, and was the only global war fought between Britain and another imperial power during the Pax Britannica, was a resounding defeat for Russia. The situation remained unresolved in Central Asia for two more decades, with Britain annexing Baluchistan in 1876 and Russia annexing Kirghizia, Kazakhstan, and Turkmenistan. For a while it appeared that another war would be inevitable, but the two countries reached an agreement on their respective spheres of influence in the region in 1878 and on all outstanding matters in 1907 with the signing of the Anglo-Russian Entente. The destruction of the Russian Navy by the Japanese at the Battle of Port Arthur during the Russo-Japanese War of 1904–05 also limited its threat to the British.

When did Russia invade the Turkish Balkans?