Umar appointed Hudheifa to the command of the campaign. Hudheifa first marched to
Zanjan. The local garrison defended itself but was eventually overpowered and the city fell. The Muslim forces proceeded to
Ardabil where the Persians did not resist and surrendered on the usual terms of
Jizya (the annual tax levied on non-Muslims). From Ardabil, the Muslim forces marched northward along the western coast of the
Caspian Sea. A confrontation ensued at the Bab area which was an important port on the Caspian Sea. The Muslims scored another victory, but for unknown reasons, Hudheifa was recalled. The Persians then launched a counterattack, causing the Muslims to abandon their forward posts in
Adurbadagan. As a response, Umar sent expeditionary forces to Adurbadagan, one led by
Bukayr ibn Abdallah and another by Utba bin Farqad. The contingent under Bukayr confronted the Persians at Jurmizan. The Persians were commanded by
Espandiyar. The battle was quite severe, the Persians were defeated and their commander Espandiyar was captured alive. Espandiyar asked Bukayr, "Do you prefer war or peace?" to which Bukayr replied that the Muslims preferred peace. Espandiyar thereupon said, "Then keep me with you till I can help you in negotiating peace with the people of Adurbadagan". The Persians went to nearby hill forts and shut themselves within. The Muslim army captured the entire area in the plains. During the year of 25 AH, the Mushaf Uthmani of Quran was created in an attempt to avoid linguistic confusion of
Qur'an which had been translated to local dialect of Adurbadagan and
Armenia. Hudhaifa warned Uthman that the translation would lose its original
Tafseer if it failed to standardise in the original
Mushaf version first, before the locals could translate and give commentary. ==Aftermath==