▁song ' s ▁historical ▁roots . ▁Later , ▁a ▁dynamic ▁of ▁class ▁and ▁circumstances ▁was ▁added ▁to ▁this . ▁The ▁most ▁prominent ▁regional ists ▁were ▁literary ▁figures ▁with ▁a ▁particular ▁interest ▁in ▁fol kl ore . ▁Carl ▁Sand burg ▁often ▁tra ve led ▁the ▁U . S . ▁as ▁a ▁writer ▁and ▁a ▁poet . ▁ ▁He ▁also ▁collected ▁songs ▁in ▁his ▁travel s ▁and , ▁in ▁ 1 9 2 7 , ▁published ▁them ▁in ▁the ▁book ▁The ▁American ▁Song bag . ▁" In ▁his ▁collections ▁of ▁folk ▁songs , ▁Sand burg ▁added ▁a ▁class ▁dynamic ▁to ▁popular ▁understand ings ▁of ▁American ▁folk ▁music . ▁This ▁was ▁the ▁final ▁element ▁of ▁the ▁foundation ▁upon ▁which ▁the ▁early ▁folk ▁music ▁rev ival ists ▁constructed ▁their ▁own ▁view ▁of ▁American ism . ▁Sand burg ' s ▁working ▁class ▁Americans ▁joined ▁with ▁the ▁eth n ically , ▁ra cially , ▁and ▁region ally ▁diverse ▁citizens ▁that ▁other ▁sch ol ars , ▁public ▁intellect uals , ▁and ▁folk lor ists ▁celebrated ▁their ▁own ▁definitions ▁of ▁the ▁American ▁folk , ▁definitions ▁that ▁the ▁folk ▁rev ival ists ▁used ▁in ▁construct ing ▁their ▁own ▁understanding ▁of ▁American ▁folk ▁music , ▁and ▁an ▁over arch ing ▁American ▁identity ". ▁ ▁Prior ▁to ▁the ▁ 1 9 3 0 s , ▁the ▁study ▁of ▁folk ▁music ▁was ▁primarily ▁the ▁province ▁of ▁sch ol ars ▁and ▁collect ors . ▁ ▁The ▁ 1 9 3 0 s ▁saw ▁the ▁beg inn ings ▁of ▁larger ▁scale ▁them es , ▁common al ities