The Ottoman Empire had maintained military parity with Russia until the second half of the eighteenth century, but by the 1820s the Ottoman armies were unable to put down the Greek War of Independence in southern Greece. The great powers of Europe decided to intervene and assist Greece with its independence. After the Battle of Navarino and the Russo-Turkish War (1828–29), in which the Russian army first crossed the Balkan Mountains and took Adrianople, Turkey recognized the independence of Greece and the transition of the Black Sea coast of the Caucasus to Russia. Thus Greece became the first independent country created out of a section of the Ottoman Empire. Russian Empire aspirations for a section of the empire and bases on Russia's southern flank provoked British fears over naval domination of the Mediterranean and control of the land route to the Indian Subcontinent.