Sentence:  Besides showing no inclination , apparently , to absent himself from his native region even for short periods , and in addition writing a shelf of books set in the region , he has handled in those books an astonishingly complete list of matters which have <WSD>been</WSD> important in the South during the past hundred years . 
Meaning of the word marked with <WSD> tags:  have the quality of being; (copula, used with an adjective or a predicate noun)