Monks from the Gengenbach monastery, located downstream of the Kinzig, founded Zell am Harmersbach; it takes its name from a monk's cell. The first settlement was located slightly higher up, where St. Symphorian stands today. Zell was first mentioned in 1139 - in a confirmation of ownership by Pope Innocent II for the Gengenbach abbot - as "cella". The rule over Zell arose from the Gengenbach bailiwick. It came from the Zähringen, the Staufers, the Geroldseckers and the bishops of Strasbourg after the interregnum to the Habsburg Rudolf I. Under the Habsburgs, Zell became a free imperial city at the beginning of the 14th century. With the mediatization through the Imperial Deputation Act in 1803, it lost imperial immediacy, and with the Peace of Pressburg in 1805 it fell to the Grand Duchy of Baden. Ecclesiastically, it passed from the Diocese of Strasbourg to the Archdiocese of Freiburg in 1921. The parish church of Zell was first documented in 1206, when the Strasbourg bishop Henry II of Veringen granted Gengenbach the right to fill the parish with one of his monks. The veneration of Saint Symphorian, who was martyred in Autun in Burgundy under Marcus Aurelius, Roman Emperor from 161 to 180, also originated in Gengenbach. The Benedictines of Gengenbach had brought the veneration with them from their mother monastery of Gorze in Lorraine. Numerous churches and monasteries in France have him as their patron, including the Zell church in the Archdiocese of Freiburg, since 1666, when a visitation protocol states:
“Huis parochialis ecclesiae patronus coeli est s. Symphorianus, terrenus vero decimator et collator abbas gengenbacensis; "It has three chapels, one in Gambach dedicated to the holy virgin, the second in Kúrnbach to the archangel Michael, and the third in Enterspach; the living creatures have 800 circiter.
The heavenly patron of this parish is Saint Symphorian, the earthly lord of tithes and collation is the Gengenbach abbot; it has three chapels, one in Gambach dedicated to the most holy virgin; the second in Kirnbach to the holy archangel Michael; the third in Entersbach; it has about 800 souls."