Rubuta ci gaba ga wannan sakin layi - Amsterdam da De Graeff sun kasance a saman ikon su kuma a 1656 sun kafa wani balaguro a karkashin Michiel de Ruyter zuwa Bahar Rum da - a cikin Charles X Gustav na Yaren mutanen Sweden yaki da Poland
- wani a karkashin Jacob van Wassenaer Obdam zuwa Tekun Baltic. Abin farin ciki ga Netherlands, wannan yaƙin ya ƙare a cikin Danzig da aka ayyana tsaka tsaki. Shugabannin gari huɗu masu ƙarfi sun yanke shawarar aika Coenraad van Beuningen zuwa Copenhagen don zuga Denmark zuwa yaƙi da Sweden. Ga mamakin kowa, a tsakiyar hunturu Sarkin Sweden ya tsallaka daga Jutland, a fadin Babban Belt, zuwa Copenhagen. A cikin tafiya ta biyu don sauƙaƙe Copenhagen, Witte de With ya shiga cikin Yaƙin Sound. Cornelis de Graeff ya shirya don fara yaki da Sweden, a kan shawarar da Grand Pensionary. Lokacin da Charles X ya mutu ba zato ba tsammani a shekara ta 1660, Sweden ta yi zaman lafiya. Amsterdam kuma ta aika da Admiral Michiel de Ruyter a kan Ingilishi, a kan umarnin majalisa na Netherlands. Duk da waɗannan bambance-bambance a cikin kusanci da De Witt, shi da De Graeff sun kasance cikin kyakkyawan yanayi. De Witt a 1660 ya lura da Cornelis: "tare da mutumin Zuidpolsbroek, a cikin komai ba wani abu bane".