▁Italy . ▁Portugal ' s ▁presence ▁in ▁Africa ▁as ▁an ▁imperial ▁power ▁last ed ▁until ▁the ▁ 1 9 7 0 s , ▁when ▁the ▁last ▁of ▁its ▁former ▁colon ies ▁declared ▁independence ▁after ▁years ▁of ▁war . ▁ ▁The ▁Atlantic ▁Ocean ▁had ▁long ▁been ▁all ▁but ▁im pen et rable ▁to ▁the ▁g alle ys ▁that ▁p lied ▁the ▁Mediter rane an . ▁That ▁any ▁ship ▁needed ▁to ▁pass ▁thousands ▁of ▁kilom eters ▁of ▁water less ▁desert ▁before ▁reaching ▁any ▁populated ▁regions ▁also ▁made ▁trade ▁impossible . ▁These ▁bar riers ▁were ▁overcome ▁by ▁the ▁development ▁of ▁the ▁car avel ▁in ▁Europe . ▁Pre viously , ▁trade ▁with ▁Sub - S ah aran ▁Africa ▁could ▁only ▁be ▁conducted ▁through ▁North ▁African ▁middle men . ▁Now ▁Europe ans ▁could ▁trade ▁directly ▁with ▁the ▁Afr icans ▁themselves . ▁ ▁This ▁valuable ▁trade ▁lead ▁to ▁rapid ▁change ▁in ▁West ▁Africa . ▁The ▁region ▁had ▁long ▁been ▁agricult ur ally ▁product ive ▁and , ▁especially ▁in ▁western ▁Niger ia , ▁dens ely ▁populated . ▁The ▁massive ▁prof its ▁from ▁trade ▁and ▁the ▁arrival ▁of ▁guns ▁lead ▁to ▁significant ▁central ization ▁and ▁a ▁number ▁of ▁states ▁formed ▁in ▁the ▁region ▁such ▁as ▁the ▁Ash anti ▁Confeder acy ▁and ▁Kingdom ▁of ▁Ben in . ▁These ▁states ▁became ▁some ▁of ▁the ▁wealth iest ▁and ▁most ▁advanced ▁in ▁Africa . ▁We alth y ▁mer ch ants ▁began ▁to ▁send ▁their ▁children ▁to ▁European ▁univers ities ▁and ▁their ▁well ▁armed ▁standing ▁arm ies ▁could ▁challenge ▁European ▁forces . ▁ ▁Many ▁West -