The ancient heartland of the Sabines was in the Tiber valley.  The people of this territory  had a long history of links with Rome [rape of the Sabine women; two kings of Rome, Numa Pompilius (traditionally 716-674 BC) and Ancus Marcius (traditionally 641-167 BC)].

At some time before recorded history, the Sabines extended their territory to the north, into the region that had probably belonged to the ancient Umbrians.  Strabo describes the tradition relating to this migration:

1. “The Sabini, since they had long been at war with the Ombrici, vowed (just as some of the Greeks do) to dedicate everything that was produced that year; and, on winning the victory, they partly sacrificed and partly dedicated all that was produced.  Then a dearth ensued, and someone said that they ought to have dedicated the babies too.  This they did, and devoted to Mars all the children born that year; and these children, when grown to manhood, they sent away as colonists, and a bull led the way; and when the bull lay down to rest in the land of the Opici (who, as it chanced, were living only in villages), the Sabini ejected them and settled on the spot, and, in accordance with the utterance of their seers, slaughtered the bull as a sacrifice to Mars who had given it for a guide.  It is reasonable to suppose therefore that their name "Sabelli" is a nickname derived from the name of their forefathers” (5:4).  
   

Strabo might mean here that the”Sabelli” (little Sabines) were the sons of “bellum” (war).  He is describing the tradition of the “ver sacrum” (sacred spring), a ritual in which sections of ancient Italic communities that faced famine were sent to found new colonies in order to avoid over-population.  In this instance, Sabines from Lower Sabinum apparently followed the ritual when colonising the land of the “Opici” in the Apennines.

Dionysius of Halicarnassus is the other main authority on the Sabine settlement of the area around Rieti, just across the Nera from modern Umbria:

1. ✴He presents two traditions:
   

2. -“Zenodotus of Troezen, [an ancient Greek historian] relates that the Umbrians ... first dwelt in the Reatine territory ... and that, being driven from there by the Pelasgians, they came into the country that they now inhabit, and changed their name ... from Umbrians to Sabines. 
   

3. -But Porcius Cato says that the Sabine race received its name from Sabus, the son of Sancus, a divinity of that country, and that this Sancus was by some called Jupiter Fidius.  He says that the Sabines’ first place of abode  was ... near the city of Amiternum; and from there they made an incursion ... into the Reatine territory, which was inhabited by the Aborigines together with the Pelasgians, and took their most famous city, Cutiliae, by force of arms and occupied it; and that, sending colonies out of the Reatine territory, they built many cities, in which they lived without fortifying them ...”
   

4. ✴In a later account, he explains how the Sabines or Reatines (who are nearly synonymous in this account) expelled the initial inhabitants of the territory following  their settlement of Reate and nearby Amiternum:
   

5. -“... the Sabines captured [Lista, which he had just described as the ‘mother-city of the Aborigines’] by a surprise attack, having set out against it from Amiternum by night.  Those who survived the taking of the place, after being received by the Reatines, made many attempts to retake their former home, but being unable to do so, they consecrated the country to the gods, as if it were still their own, invoking curses against those who should enjoy the fruits of it”.
   

From this base, the Sabines seem to have spread out across what became Upper Sabinium, the region that bordered Umbria at the Nera river.  Their new territory included Nursia, which is in modern Umbria: however, Nursia does not feature in classical literature until in 205 BC, when it was an ally of Rome.

1. ✴Nursia: Bishop Stephanus of Nursia attended the synod that was convened in Rome in 499, at the start of the Laurentian Schism.