▁r uling ▁coal ition ▁col lapsed ▁as ▁multiple ▁parties ▁left ▁the ▁coal ition . ▁ ▁Background ▁ ▁The ▁historic ▁election ▁result , ▁coming ▁after ▁years ▁of ▁sc and als , ▁resulted ▁in ▁the ▁L DP ▁losing ▁the ▁premi ership ▁for ▁the ▁first ▁time ▁since ▁ 1 9 5 5 . ▁The ▁ult imate ▁cause ▁of ▁the ▁L DP ' s ▁was ▁the ▁defe ction ▁of ▁key ▁polit icians ▁from ▁the ▁party ▁and ▁the ▁consequ ent ▁formation ▁of ▁two ▁break away ▁parties . ▁ ▁Prime ▁Minister ▁Ki ichi ▁Mi y az awa ' s ▁dissol ution ▁of ▁the ▁Lower ▁House ▁ ▁The ▁election ▁was ▁precip itated ▁by ▁the ▁decision ▁of ▁ 3 9 ▁L DP ▁members ▁- ▁ 3 4 ▁of ▁them ▁from ▁the ▁H ata - O za wa ▁fa ction ▁of ▁the ▁L DP , ▁four ▁from ▁the ▁fa ction ▁led ▁by ▁former ▁Foreign ▁Minister ▁Mich io ▁Wat an abe , ▁and ▁one ▁from ▁the ▁fa ction ▁led ▁by ▁former ▁state ▁minister ▁T osh io ▁Kom oto ▁- ▁to ▁vote ▁against ▁their ▁own ▁government ▁in ▁favor ▁of ▁a ▁motion ▁of ▁no ▁confidence ▁which ▁was ▁put ▁forward ▁by ▁the ▁opposition ▁in ▁a ▁pl en ary ▁session ▁on ▁June ▁ 1 8 . ▁ ▁This ▁was ▁only ▁the ▁second ▁time ▁since ▁the ▁formation ▁of ▁the ▁L DP ▁that ▁a ▁no - conf idence ▁motion ▁had ▁actually ▁succeeded . ▁In ▁the ▁previous ▁occurrence ▁in ▁the ▁May ▁ 1 9 8 0 ▁Lower ▁House ▁election , ▁ 6 9 ▁L DP ▁reb els ▁were ▁not ▁present