ers ▁of ▁the ▁slave ▁trade ▁at ▁the ▁turn ▁of ▁the ▁eigh teenth ▁century . ▁The ▁export ▁of ▁ 5 % ▁of ▁the ▁population ▁each ▁year ▁resulted ▁in ▁overall ▁population ▁decl ine . ▁Moreover , ▁since ▁the ▁majority ▁of ▁the ▁export ed ▁capt ives ▁were ▁male , ▁the ▁slave ▁trade ▁led ▁to ▁an ▁im bal ance ▁in ▁the ▁female / male ▁ratio . ▁In ▁some ▁parts ▁of ▁the ▁S lave ▁Coast ▁the ▁ratio ▁reached ▁two ▁adult ▁women ▁for ▁every ▁man . ▁Several ▁wars ▁( s ometimes ▁deliber ately ▁prov oked ▁by ▁European ▁powers ▁in ▁order ▁to ▁divide ▁and ▁rule ) ▁further ▁dist orted ▁social ▁and ▁econom ical ▁relations ▁in ▁the ▁area . ▁The ▁lack ▁of ▁earlier ▁lingu istic ▁data ▁makes ▁it ▁difficult ▁to ▁trace ▁the ▁in ev itable ▁lingu istic ▁changes ▁that ▁resulted ▁from ▁this ▁tur bul ent ▁period . ▁ ▁Col on isation ▁and ▁on wards ▁Ar ound ▁ 1 8 5 0 , ▁the ▁trans at l antic ▁slave ▁trade ▁had ▁virt ually ▁ceased . ▁As ▁the ▁g rip ▁of ▁European ▁colonial ▁powers ▁strength ened , ▁slave ▁ra iding ▁became ▁prohib ited , ▁trad ing ▁focused ▁on ▁goods ▁once ▁more ▁and ▁the ▁Europe ans ▁took ▁it ▁to ▁be ▁their ▁calling ▁to ▁Christian ize ▁the ▁colon ized ▁parts ▁of ▁Africa . ▁In ▁ 1 8 4 7 ▁the ▁Nord deutsch e ▁Miss ions - G es ellschaft ▁( Bre men ) ▁started ▁its ▁work ▁in ▁K eta . ▁ ▁In ▁ 1 8 5 7 , ▁the ▁first ▁E we ▁grammar , ▁Schl