Ranieri's legendary origin as one of the sons of Count Arduino and Countess Willa di Ugo or Gisla[further explanation needed] is in conflict with historical records.
Most sources suggest that Ranieri's father, Count Guido, was the son of Margrave Ugo, who founded the Abbey of Santa Maria in Petroio in 960, located in the territory of Perugia.
In 1014, a decree mentioned in Cronica di Farfa[4] was signed by both Margrave and Duke Ranieri in the tower of Corneto (now Tarquinia), confirming his rule over the March and the ducal territories of Spoleto.
Another decree held in Corneto that same year was overseen by a gastaldo (a magistrate) appointed by Duke and Margrave Ranieri, in support of Abbot Winizzone of Abbadia San Salvatore regarding properties owned by the abbey near the Marta River.
Additional decrees in 1015 and 1016, respectively issued from Stazzano above Pistoia and Arezzo, demonstrate Ranieri's active involvement in supporting various abbeys and religious institutions.
Additionally, a deed from December 1031 refers to certain properties near Arezzo that belonged to Ranieri, the son of Count Guido, who held the title of Margrave.