▁Christian ity ▁and ▁especially ▁w itch craft , ▁for ▁which ▁the ▁or de al ▁of ▁tang ena ▁was ▁rout in ely ▁oblig atory . ▁Between ▁ 1 8 2 8 ▁and ▁ 1 8 6 1 , ▁the ▁tang ena ▁or de al ▁caused ▁about ▁ 3 , 0 0 0 ▁death s ▁ann ually . ▁In ▁ 1 8 3 8 , ▁it ▁was ▁estimated ▁that ▁as ▁many ▁as ▁ 1 0 0 , 0 0 0 ▁people ▁in ▁I mer ina ▁died ▁as ▁a ▁result ▁of ▁the ▁tang ena ▁or de al , ▁const itut ing ▁roughly ▁ 2 0 ▁percent ▁of ▁the ▁population . ▁The ▁combination ▁of ▁regular ▁war fare , ▁disease , ▁difficult ▁forced ▁labor ▁and ▁har sh ▁measures ▁of ▁justice ▁resulted ▁in ▁a ▁high ▁mort ality ▁rate ▁among ▁soldiers ▁and ▁civ ili ans ▁al ike ▁during ▁her ▁ 3 3 - year ▁reign , ▁the ▁population ▁of ▁Mad agas car ▁is ▁estimated ▁to ▁have ▁decl ined ▁from ▁around ▁ 5 ▁million ▁to ▁ 2 . 5 ▁million ▁between ▁ 1 8 3 3 ▁and ▁ 1 8 3 9 . ▁ ▁Among ▁those ▁who ▁continued ▁to ▁res ide ▁in ▁I mer ina ▁were ▁Jean ▁Labor de , ▁an ▁entrepr ene ur ▁who ▁developed ▁m un itions ▁and ▁other ▁indust ries ▁on ▁beh alf ▁of ▁the ▁mon archy , ▁and ▁Joseph - Fran çois ▁Lam bert , ▁a ▁French ▁advent urer ▁and ▁slave ▁tr ader , ▁with ▁whom ▁then - Pr ince ▁Rad ama ▁II ▁signed ▁a ▁controvers ial