Bābak Khorramdin (Persian: بابک خرمدین, Bābak-e Khorramdin, from Middle Persian "Pāpak"/"Pābag", meaning "Young Father"; 795 or 798 – January 838) was one of the main Iranian revolutionary leaders of the Iranian Khorram-Dinān ("Those of the joyous religion"), which was a local freedom movement fighting the Abbasid Caliphate. Khorramdin appears to be a compound analogous to dorustdin "orthodoxy" and Behdin "Good Religion" (Zoroastrianism), and are considered an offshoot of neo-Mazdakism. Babak's Iranianizing rebellion, from its base in Azerbaijan in northwestern Iran, called for a return of the political glories of the Iranian past. The Khorramdin rebellion of Babak spread to the Western and Central parts of Iran and lasted more than twenty years before it was defeated when Babak was betrayed. Babak's uprising showed the continuing strength in Azerbaijan of ancestral Iranian local feelings. Etymology Bābak () is a New Persian name meaning "father", which is derived from the Middle Persian Pāpak/Pābag (𐭯𐭠𐭯𐭪𐭩), a common name in pre-Islamic Iran and also the hereditary name of the Sasanian Empire, whose founder Ardashir I (), was the son of a prince named Pabag. The original name of Babak was al-Hasan. Background Babak was born in 795 (or 798) in Bilalabad in the Mimadh district of the Ardabil area, which was part of Azerbaijan, a region in north-western Iran. The Mimadh district had provided the Sasanian marzban ("margrave") of Ardabil with troops during the Muslim conquest of Iran in 633–654, which resulted in the fall of the Sasanians and the conquest of Azerbaijan. The region was briefly occupied by the Khazars in 730–731, and had since the mid 8th century been under occupation by the Arab Rawadid clan. Azerbaijan was populated by an Iranian people known as the Adhari, who although closely related, were distinct from the Persians. They spoke Adhari, which according to the 10th-century geographer al-Maqdisi, was similar to Persian. Babak was most likely himself not of pure Persian extraction, but of Adhari. His mother Mahru (meaning "Moon-Face") was a non-Muslim wet-nurse from Azerbaijan. She is described as being "one-eyed" in Muslim sources and furthermore, by Al-Tabari, as having become pregnant with her son after being raped by a mercenary. However, these stories are more than likely fabrications created by hostile authors in order to disgrace Babak. As for the identity Babak's father, there are also multiple conflicting accounts. Al-Waqidi, as quoted by Ibn Al-Nadim, states that he was an oil-seller from