He was raised at court, his mother being a lady-in-waiting, and became the playmate of prince Magnus, Duke of Östergötland and courtier of king Gustav I of Sweden in 1556.
He was made member of the royal council by Eric XIV of Sweden and served as a military commander in the Northern Seven Years' War.
[1] The plot did not materialize as de Mornay lost his nerve and never gave the sign to the mercenaries to take action.
[1] The two royal sisters and their brother Charles were somewhat compromised, though neither they, Bielke, Banér or De la Gardie was openly accused of their suspected involvement.
[1] When the king and queen visited their son Sigismund III Wasa in Reval in 1589, he and Axel Bielke was appointed to serve as regent during their absence.