Thanks to the geographical closeness to the West and to communications with nearby countries' enlightenment movements, Tabriz became the centre of the Iranian Constitutional Revolution movements between 1905 and 1911, which led to the establishment of a parliament in Iran and the formation of a constitution. Sattar Khan and Bagher Khan, two Tabrizi reformists who led Tabriz people's solidarity against the absolute monarchy, had a great role in achievement to the goals of Iran's constitutional revolution. In 1909, Tabriz was occupied by the Russian forces. Four months after the constitutional revolution's success, in December 1911, the Russians reinvaded Tabriz. After crushing the local resistance by invading Russian troops, they started suppressing the constitutional revolutionaries and residents of the city. Following the invasion, Russian troops executed about 1,200 of Tabriz residents. As a result of the campaign, Tabriz was occupied by the Russian forces between 1911 and 1917.