Sentence:  Those with Celtic legendry in their heritage—mainly the Scotch-Irish element of New Hampshire, and their kindred who had settled in Vermont on Governor Wentworth's colonial grants—linked them vaguely with the malign fairies and “little people” of the bogs and <WSD>raths</WSD>, and protected themselves with scraps of incantation handed down through many generations. 
Meaning of the word marked with <WSD> tags:  A walled enclosure, especially in Ireland; a ringfort built sometime between the Iron Age and the Viking Age.