gained control over the northern areas of Iran, which included the cities of Tabriz, Tehran, Mashad, and Isfahan. The British were given the southeastern region and control of the Persian Gulf, and the territory between the two regions was classified as neutral territory. Russia's influence in northern Iran was paramount from the signing of the Anglo-Russian Convention of 1907 until the outbreak of World War I in 1914. During this time period, it stationed troops in Iran's Gilan, Azerbaijan and Khorasan provinces, and its diplomatic offices (consulates) in these parts wieleded considerable power. These consulates dominated the local Iranian administration and in some circumstances even collected local taxes. Starting in the same year as the Anglo-Russian Convention, unpremeditated Russian colonization commenced in Mazandaran and Astarabad provinces. Then, in 1912, Russian foreign policy officially adopted the plan to colonize northern Iran. At the outbreak of World War I, there were most likely some 4,000 Russian settlers in Astarabad and Mazandaran, whereas in northeastern Iran the Russians had founded a minimum of 15 Russian villages. During the reign of Nicholas II of Russia, Russian occupational troops played a major role in the attempted Tsarist suppression of the Iranian Constitutional Revolution. In the dawn of the outbreak of World War I, Russian occupational forces occupied Qajar Iran's Azerbaijan province as well as the entire north and north-east of the country, and amounted to circa twenty thousand. Following the start of the Persian Campaign of World War I, the number of Russian troops in Iran moderately grew to some eighty or ninety thousand. As a result of the major Anglo-Russian influence in Iran, at a high point, the central government in Tehran was left with no power to even select its own ministers without the approval of the Anglo-Russian consulates. Morgan Shuster, for example, had to resign under British and Russian diplomatic pressure on the Persian government. Shuster's book The Strangling of Persia: Story of the European Diplomacy and Oriental Intrigue That Resulted in the Denationalization of Twelve Million Mohammedans is an account of this period, criticizing the policies of Russian and Britain in Iran. These, and a series of climaxing events such as the Russian shelling of Mashad's Goharshad Mosque in 1911, and the shelling of the Persian National Assembly by the Russian Colonel V. Liakhov, led to a surge in widespread anti-Russian sentiments across the nation. Soviet Union Pahlavi–Soviet Union One result