Political map of Europe & the Mediterranean 14 September 1826 (Russo-Persian War of 1826–28): In 1826 Russian troops encroached on Persian territory in Armenia, disregarding the direct orders of the Tsar—who was focused on the Greek revolution against the Ottoman Empire (Greek War of Independence)—not to provoke Persia. The Persians responded by invading the Russian Caucasus, inciting uprisings among local rulers and tribes (Russo-Persian War (1826–28)). Despite initial setbacks, Russia eventually gained the upper hand and in 1828 forced Persia to cede its Armenian territories (Treaty of Turkmenchay).