Turning Points in the history of Azerbaijan:
From the formation of Persian Empire Azerbaijan was a part it. Azerbaijan was divided as a result of two wars between Russia & Persia:
        1813-Treaty of Gulistan, resulted in the separation of Baku, Shirvan, Shaki, Karabagh and part of
        1827-Tnreaty of Turkmanchay, it produced the border agreement as it is today

The separated parts stayed under Russian Empire, and then The Soviet. However
        1918-1920 Short period of independancy as the Democratic Republic of Azerbaijan

The articles below and their correspondence links will give you some ideas regarding the socio-political feelings of the Azeris in Iran.