Behbahan (Persian: بهبهان, also Romanized as Behbahān and Behbehān) is a city in and the capital of Behbahan County, Khuzestan Province, Iran. At the 2012 census its population was 310,000.
To the north of the city lie the ruins of the ancient city Arjan, built during the Sassanian period, where important remnants from the Elamite era can be found.
The people of Behbahan (Behbahanis) speak a Persian dialect distinct to their group, as well as Sassanid language Middle Persian, ...see more and may still use words of Khuzi origin, the language of the original inhabitants of Khuzestan. Behbahanis claim various lines of descent: from the ancient peoples of Arrajan - the Persians / nobility . The inhabitants of the suburban districts are primarily of Lurs background. The majority of Behbahanis are remains of Arrajan (Arjan/Argan) after an earthquake destroyed a dam, which led to the flooding of the city. People of Arrajan were originally Zoroastrian during the elamite period, and later on converted to Islam. The details of how or when they converted are unclear. According to the elderly of the city and the oral history, the current population of Behbahan consists of a mixture of 60% zoroastrian background, and 40% others. They are mostly Muslims, even those who still observe sabbath to be the holy day of the week. However, a large Baha'i minority can be noticed.