as aki . ▁By ▁then , ▁trade ▁with ▁Japan ▁was ▁a ▁Portuguese ▁mon opol y ▁under ▁the ▁rule ▁of ▁a ▁Captain . ▁Because ▁the ▁Portuguese ▁established ▁themselves ▁in ▁Mac au , ▁Chinese ▁commercial ▁relations , ▁mainly ▁the ▁silver ▁trade ▁with ▁Japan , ▁were ▁improved ▁under ▁John ▁III ' s ▁rule . ▁ ▁After ▁the ▁voyage ▁of ▁Ferdinand ▁Mag ellan , ▁the ▁Crown ▁of ▁Cast ile ▁claimed ▁the ▁recently ▁discovered ▁Mal u ku ▁Islands . ▁In ▁ 1 5 2 4 , ▁a ▁conference ▁of ▁exper ts ▁( cart ograph ers , ▁cosm ograph ers , ▁pil ots , ▁etc .) ▁was ▁held ▁to ▁solve ▁the ▁dispute ▁caused ▁by ▁the ▁difficulty ▁of ▁determ ining ▁the ▁mer id ian ▁agreed ▁to ▁in ▁the ▁Tre aty ▁of ▁T ord es illas . ▁The ▁Portuguese ▁deleg ation ▁sent ▁by ▁John ▁III ▁included ▁names ▁such ▁as ▁Ant ón io ▁de ▁A ze ved o ▁C out inho , ▁Di ogo ▁L op es ▁de ▁Se que ira , ▁L opo ▁Hom em ▁and ▁Sim ão ▁Fern and es . ▁The ▁dispute ▁was ▁settled ▁in ▁ 1 5 2 9 ▁by ▁the ▁Tre aty ▁of ▁Zar ago za , ▁signed ▁by ▁John ▁III ▁and ▁Charles ▁I ▁of ▁Spain . ▁The ▁Portuguese ▁paid ▁ 3 5 0 , 0 0 0 ▁gold ▁duc ados ▁to ▁Spain ▁and ▁secured ▁their ▁presence ▁in ▁the ▁islands , ▁which ▁not ▁have ▁been ▁a ▁necessity , ▁as ▁Portugal ▁was ▁actually ▁entitled ▁to ▁the ▁islands ▁according ▁to ▁the ▁Tre aty ▁of ▁T ord es illas .