 Longfellow often used didacticism in his poetry , though he focused on it less in his later years . Much of his poetry imparts cultural and moral values , particularly focused on promoting life as being more than material pursuits . Longfellow also often used allegory in his work . In " Nature " , for example , death is depicted as bedtime for a cranky child . Many of the metaphors he used in his poetry as well as subject matter came from legends , mythology , and literature . He was inspired , for example , by Norse mythology for " The Skeleton in Armor " and by Finnish legends for The Song of Hiawatha . In fact , Longfellow rarely wrote on current subjects and seemed detached from contemporary American concerns . Even so , Longfellow , like many during this period , called for the development of high quality American literature . In Kavanagh , a character says : 
