Catharine Montour was a leader of the local Seneca Native American community when it was destroyed by the Sullivan Expedition in 1771. Over time, the town was named after her by the descendants of the White settlers who set up on the site of the former longhouses.
This mural of Catharine Montour is on the side of the Masonic Lodge in town. It depicts Montour, as well as a burial mound and headstone that memorializes her. Several historical sources I read have argued that there's some disagreement over whether she ever returned, or whether she stayed in Canada, where she fled after her home was destroyed by Sullivan's soldiers.