▁and ▁ 1 9 7 0 ▁as ▁a ▁professor ▁and ▁eventually ▁served ▁as ▁Chair ▁of ▁the ▁Department ▁of ▁History ▁during ▁his ▁last ▁four ▁years . ▁In ▁ 1 9 7 0 , ▁Ber th rong ▁accepted ▁a ▁position ▁as ▁Head ▁of ▁the ▁Department ▁of ▁History ▁at ▁Pur due ▁University , ▁a ▁position ▁he ▁occupied ▁until ▁ste pping ▁down ▁to ▁res ume ▁full - time ▁teaching ▁duties ▁in ▁ 1 9 8 5 . ▁ ▁Death ▁Donald ▁J . ▁Ber th rong ▁died ▁on ▁July ▁ 3 0 , ▁ 2 0 1 2 ▁in ▁Alexand ria , ▁Virginia ▁from ▁p neum onia . ▁He ▁is ▁buried ▁at ▁the ▁Columb arium ▁at ▁Ar ling ton ▁National ▁C emetery ▁next ▁to ▁his ▁wife , ▁Rh io ▁Ber th rong . ▁ ▁Writ ings ▁Donald ▁Ber th rong ' s ▁accomplish ments ▁include ▁not ew orth y ▁and ▁significant ▁contributions ▁to ▁the ▁history ▁of ▁the ▁American ▁West ▁such ▁as ▁The ▁Southern ▁Che y ennes ▁( 1 9 6 3 ) ▁and ▁The ▁Che y enne ▁and ▁A rap aho ▁Or de al : ▁Res ervation ▁and ▁Agency ▁Life ▁in ▁the ▁Indian ▁Territ ory , ▁ 1 8 7 5 - 1 9 0 7 ▁( 1 9 7 6 ). ▁ ▁Ber th rong ’ s ▁The ▁Southern ▁Che y ennes ▁is ▁a ▁detailed ▁eth n oh istory ▁of ▁the ▁Southern ▁Che y ennes ▁between ▁ 1 8 4 0 ▁and ▁ 1 8 7 5 . ▁His ▁work ▁serves ▁as ▁a ▁challenge ▁and ▁a ▁supp