im y ō ▁converts . ▁The ▁direct ▁trigger ▁which ▁is ▁said ▁to ▁have ▁sp ur red ▁the ▁im position ▁of ▁s ak oku ▁was ▁the ▁Sh im ab ara ▁Reb ell ion ▁of ▁ 1 6 3 7 – 3 8 , ▁an ▁u pr ising ▁of ▁ 4 0 , 0 0 0 ▁mostly ▁Christian ▁pe as ants . ▁In ▁the ▁after math , ▁the ▁sh og un ate ▁accused ▁mission aries ▁of ▁inst ig ating ▁the ▁re bell ion , ▁exp elled ▁them ▁from ▁the ▁country , ▁and ▁strictly ▁b anned ▁the ▁religion ▁on ▁penalty ▁of ▁death . ▁The ▁remaining ▁Japanese ▁Christians , ▁mostly ▁in ▁Nag as aki , ▁formed ▁under ground ▁communities ▁and ▁came ▁to ▁be ▁called ▁K ak ure ▁Kir ish itan . ▁ ▁All ▁contact ▁with ▁the ▁outside ▁world ▁became ▁strictly ▁reg ulated ▁by ▁the ▁sh og un ate , ▁or ▁by ▁the ▁domains ▁( T s ush ima , ▁M ats um ae , ▁and ▁S ats uma ) ▁assigned ▁to ▁the ▁task . ▁Dutch ▁trad ers ▁were ▁permitted ▁to ▁continue ▁commerce ▁in ▁Japan ▁only ▁by ▁agree ing ▁not ▁to ▁eng age ▁in ▁mission ary ▁activities . ▁Today , ▁the ▁Christian ▁percentage ▁of ▁the ▁population ▁( 1 %) ▁in ▁Japan ▁remains ▁far ▁lower ▁than ▁in ▁other ▁East ▁Asian ▁countries ▁such ▁as ▁China ▁( 3 % ), ▁Vietnam ▁( 7 % ), ▁South ▁Korea ▁( 2 9 %) ▁and ▁the ▁Philippines ▁( over ▁ 9 0 %). ▁ ▁The ▁s ak oku ▁policy ▁was ▁also ▁a ▁way ▁of