Important battles also took place in the South China Sea, initially with combined fleets of Dutch and English vessels, and subsequently exclusively Dutch ships assaulting Macau. Dutch attempts to capture Macau, to force China to replace the Portuguese or to settle the Pescadores failed, in part because of the long-standing diplomacy between the Portuguese and the Ming, but the Dutch were ultimately successful in acquiring the monopoly of trade with Japan. Meanwhile, the Dutch were unable in four attempts to capture Macau from where Portugal monopolised the lucrative China–Japan trade.