▁as ▁ 3 8 0 0 ▁B . P . ▁in ▁parts ▁of ▁the ▁region . ▁ ▁Middle ▁Wood land ▁period ▁( 2 0 0 ▁B CE ▁– ▁ 5 0 0 ▁CE ) ▁ ▁The ▁beginning ▁of ▁the ▁Middle ▁Wood land ▁saw ▁a ▁shift ▁of ▁settlement ▁to ▁the ▁Inter ior . ▁As ▁the ▁Wood land ▁period ▁progress ed , ▁local ▁and ▁inter - reg ional ▁trade ▁of ▁ex otic ▁materials ▁greatly ▁increased ▁to ▁the ▁point ▁where ▁a ▁trade ▁network ▁covered ▁most ▁of ▁the ▁Eastern ▁Wood lands . ▁Through out ▁the ▁S out heast ▁and ▁north ▁of ▁the ▁Ohio ▁River , ▁bur ial ▁m ounds ▁of ▁important ▁people ▁were ▁very ▁elaborate ▁and ▁contained ▁a ▁variety ▁of ▁mort u ary ▁g ifts , ▁many ▁of ▁which ▁were ▁not ▁local . ▁Among ▁the ▁trad ed ▁materials ▁were ▁co pper ▁from ▁the ▁Lake ▁Super ior ▁depos its ; ▁silver ▁from ▁Lake ▁Super ior ▁and ▁especially ▁Ontario ; ▁gal ena ▁from ▁Missouri ▁and ▁Illinois ; ▁m ica ▁from ▁the ▁southern ▁App al ach ians ; ▁ch ert ▁from ▁various ▁places ▁including ▁Ohio , ▁Indiana , ▁and ▁Illinois ; ▁pip estone ▁from ▁Ohio ▁and ▁Illinois ; ▁all ig ator ▁teeth ▁from ▁the ▁lower ▁Mississippi ▁Valley ▁east ward ▁to ▁Florida ; ▁marine ▁shell s , ▁especially ▁wh el ks , ▁from ▁the ▁south ▁Atlantic ▁and ▁G ulf ▁coast s ; ▁Kn ife ▁River ▁ch al ced ony ▁from ▁North ▁Dak ota ; ▁and ▁obs id ian ▁from ▁Y ellow stone ▁in ▁Wy oming . ▁The ▁most ▁arch ae olog