▁the ▁support ▁given ▁by ▁Lé once ▁Ros enberg , ▁Cub ism ▁re emer ged ▁as ▁a ▁central ▁issue ▁for ▁artists ▁after ▁four ▁years ▁of ▁war . ▁Ros enberg ▁found ▁himself ▁finan cially ▁ru ined ▁but ▁exhib ited ▁the ▁works ▁he ▁owned ▁at ▁his ▁newly ▁opened ▁Galerie ▁de ▁L ' E ff ort ▁Mod erne ▁( also ▁known ▁as ▁Galerie ▁Lé once ▁Ros enberg ) ▁at ▁ 1 9 , ▁rue ▁de ▁la ▁Ba ume , ▁located ▁in ▁the ▁elegant ▁and ▁fashion able ▁ 8 th ▁arr ondissement ▁of ▁Paris . ▁The ▁gallery ▁was ▁open ▁to ▁all ▁forms ▁of ▁Cub ist ▁and ▁Abstract ▁art . ▁What ▁followed ▁would ▁be ▁a ▁series ▁of ▁major ▁one - man ▁exhib itions — including ▁works ▁created ▁between ▁ 1 9 1 4 ▁and ▁ 1 9 1 8 ▁by ▁almost ▁all ▁the ▁major ▁Cub ists . ▁ ▁The ▁first ▁solo ▁exhibition ▁was ▁held ▁in ▁March ▁ 1 9 1 8 , ▁featuring ▁works ▁by ▁August e ▁Her bin . ▁In ▁December ▁of ▁the ▁same ▁year , ▁Ros enberg ▁launched ▁a ▁series ▁of ▁Cub ist ▁exhib itions , ▁beginning ▁with ▁Henri ▁Laur ens , ▁followed ▁in ▁January ▁ 1 9 1 9 ▁with ▁an ▁exhibition ▁of ▁Cub ist ▁paint ings ▁by ▁Jean ▁Met z inger , ▁Fern and ▁Lé ger ▁in ▁February , ▁Georges ▁Bra que ▁in ▁March , ▁Juan ▁Gr is ▁April , ▁G ino ▁Sever ini ▁May , ▁and ▁Pablo ▁Pic asso ▁in ▁June , ▁mark ing ▁the ▁clim ax ▁of ▁the ▁campaign . ▁This ▁well -