Nyorai kupfuurira kweiyi ndima - Cort Sivertsen akaberekerwa muBrevik, Norway, mwanakomana wemutengesi. Pazera ramakore gumi nemashanu akapinda mubasa rehondo yeDutch; muna 1639 akarwa pasi paLieutenant-Admiral Maarten Tromp paHondo yeDowns
. Muna 1642 akanga ari mukuru mukuru pa"Grote St. Joris", ngarava yechiDutch yakashandiswa neboka reVenice se"San Giorgio Grande". Sivertsen akazvidaidza kuti "Adelborst" munguva iyi, zita rechiDutch rinoreva "cadet". Muna 1645 akava kaputeni we"San Giorgio" ndokupinda mubasa rakazara reVenetian. Muna 1650 "San Giorgio" yakava ngarava huru uye Sivertsen nokudaro kaputeni mureza. Mukurwisa ngarava dzeTurkey musi wa13 Chivabvu 1654 padyo neDardanelles iye akaputsa nechikepe chake mutsara wevaTurkey uye akanyudza gumi neshanu vavo; zuva rakatevera varwi veTurkey veTenedos vakazvipa kwaari. Nokuda kwaikoku akaitwa knight muOrder yaSaint Mark; seneti yeVenetian yakamupa mubayiro wegore negore we1400 golden ducats. Muna 1660 akagadzwa kuva Vice-Admiral.