The county or march of Turin (sometimes "march of Susa") was founded in 941 by Hugh of Italy, who appointed Arduin Glaber as its governor. Arduin had captured Turin and the Susa Valley from the Saracens. By subsequent conquests, Arduin came to govern a vast march with the margravial title (consistently used from 962).
The march, first called the marca Arduinica, was formed by a reorganisation of the territory of the regnum Italicum into three margraviates for three great families: the marca Arduinica, marca Aleramica, and marca Obertenga.
Ulric Manfred II, the most powerful margrave, left the march to his daughter Adelaide, who married Otto of Savoy in 1046. Adelaide's children and grandchildren through Otto co-governed the march with her after Otto's death, but after her death in 1090, the comital authority of the city of Turin was invested in the bishop (1092) and the city itself was granted a commune (1091). The margravial lands were absorbed into Savoy, of which Turin became the eventual capital some centuries later.
In 1076, the Emperor Henry IV, at odds with most of the local nobility and the church, appointed his son Conrad Margrave of Turin at the age of two. This power was never effectual and the title was purely nominal, as he was his father's heir.
All the margraves were of the Arduinici family.