between 1907 and 1917 the Persian question was of vital importance in Anglo-Russian relations. It was dealt with in the most important section of the Anglo-Russian convention of 1907, which formed the basis of the Anglo-Russian entente. Persia was one of the few areas of the world where Britain and Russia could co-operate to establish a basis for a wider underetandin:,. The crucial years in the development of Anglo-Russian policy in Persia were 1909 to 1915. The exchange of the pro-Russian Muhammad 'Ali Shah for a government unsympathetic to Russian interests was the first blow at Anglo-Russian cooperation, because the Persian capital lay within the Russian zone. In 19lu the interference of the Germans and the opposition of the Persian nationalists prevented Britain and Russia from trying to establish a strong hold over the government. The Potsdam agreement removed Germany as a political threat in Persia until the world war. The Shuster crisis eliminated the ma lie. Britain was willing to Co as far as helping to remove Shuster, but would not co-operate to restore Muhammad 'Ali. The removal of the Germans and the nationalists from the Persian scene laid bare the Anglo-Russian conflict.The failure of a further attempt to establish a pro-Russian influence at Tehran late in 1912, led to the breakdown of co-operation in Persia. ttussian activity in 191) was concentrated on supporting pro-Russian local authorities, having failed in Tehran. After the ! +alkan wars, attention was again directed to Persia in 1914, because of the urgent need to strengthen the entente and solve disputes between the two powers. The . sritish in ! larch 1915 were finally forced to accept a change of policy which would concentrate the attention of the two powers on their respective spheres of influence, and not on co-operating to support the central Persian government.