▁Pale mb ang ▁Sultan ate ▁sent ▁for ▁exper ts ▁in ▁Mal ay ▁Pen ins ula ▁and ▁China . ▁The ▁Dutch ▁East ▁India ▁Company ▁managed ▁to ▁secure ▁a ▁mon opol istic ▁tin ▁purchase ▁agreement ▁in ▁ 1 7 2 2 , ▁but ▁host ilities ▁began ▁to ▁develop ▁between ▁the ▁Sultan ▁and ▁the ▁Dutch . ▁During ▁the ▁British ▁In vas ion ▁of ▁Java ▁in ▁ 1 8 1 1 , ▁then - S ultan ▁Mah m ud ▁Bad ar ud din ▁attacked ▁and ▁mass ac red ▁the ▁staff ▁of ▁the ▁Dutch ▁post ▁on ▁the ▁island . ▁He ▁was ▁later ▁de posed ▁and ▁executed ▁by ▁the ▁British . ▁His ▁successor ▁c eded ▁Bang ka ▁to ▁Britain ▁in ▁ 1 8 1 2 , ▁but ▁in ▁ 1 8 1 4 ▁Britain ▁ex changed ▁it ▁with ▁the ▁Dutch ▁for ▁C och in ▁in ▁India ▁following ▁the ▁Ang lo - D utch ▁Tre aty ▁of ▁ 1 8 1 4 . ▁ ▁Ar ound ▁the ▁late ▁years ▁of ▁the ▁ 1 8 th ▁century , ▁Bang ka ▁was ▁an ▁important ▁production ▁center ▁of ▁tin ▁in ▁Asia , ▁with ▁annual ▁outputs ▁hover ing ▁around ▁ 1 , 2 5 0 ▁tons . ▁In ▁ 1 9 3 0 ▁Bang ka ▁had ▁a ▁population ▁of ▁ 2 0 5 , 3 6 3 . J apan ▁occupied ▁the ▁island ▁from ▁February ▁ 1 9 4 2 ▁to ▁August ▁ 1 9 4 5 ▁during ▁World ▁War ▁II . ▁The ▁Japanese ▁military ▁perpet r ated ▁the ▁Bang ka ▁Island ▁mass acre