Jamieson, Fausset & Brown, on 1Chr 2:23

“And he took Gessur, and Aram the towns of Jair, and Canath, and the villages thereof, threescore cities. All these, the sons of Machir father of Galaad.”

“he took--rather "he had taken." This statement is accounting for his acquisition of so large a territory; he got it by right of conquest from the former possessors. Kenath--This place, along with its group of surrounding villages, was gained by Nobah, one of Jair's officers sent by him to capture it (Num 32:1-2). All these belonged to the sons of Machir--In their number Jair is included as having completely identified himself by his marriage and residence in Gilead with the tribe of Manasseh.”

Imported from an open dataset — not yet checked against the printed edition.