His father, Hans Klasson Bjelkenstjerna, who also was a high-ranking naval officer, died when his son was only 5 years old, leaving him to be raised by relatives.

Young Bjelkenstjerna soon grew up and followed in his father's footsteps, joining the Swedish navy.

He participated in the sea campaigns against the Danish and Dutch fleets, in particular Battle of Colberger Heide (1644), and the escape from the Kiel Fjord where the Danish fleet tried to trap the Swedish squadrons.

Queen Christina I granted him the barony of Pyhäjoki in the Northern Ostrobothnia region of Finland.

Tack för hvar dag vi varit tillsammans!» which translates to English as "Farewell, my honourable Bjelkenstjerna!