Between 1558 and 1563 he was one of Duke John's closest advisors. He then served under King Erik XIV, and was made a colonel during the Livonian War in October 1563 and Governor of Estonia and highest commander of the Swedish Infantry in the Baltic Dominions of Sweden. He defeated a German mercenary force near Tallinn in 1565. He was named to the position of High Councillor in 1566. In 1565 he became governor of Reval and over Livonia. He lost command in 1567 after the failure of the Swedish siege of Narva in 1579 and was replaced by Pontus de la Gardie (c. 1520 – 1585).