The Seyler family (also spelled Seiler) is a Swiss family, originally a patrician family from Liestal near Basel. Family members served as councillors and Schultheißen of Liestal from the 15th century, later also as members of the Grand Council of Basel. A Hamburg branch descended from the banker and renowned theatre director Abel Seyler became by marriage a part of the Berenberg banking dynasty, co-owners of Berenberg Bank and part of Hamburg's ruling class of Hanseaten.