 So in 1626 he moved to Thônes, where Duke Charles Emmanuel of Savoy allowed to hold Lutheran church services.In the summer of 1627 he was appointed lieutenant general of the Danish army by King Christian IV of Denmark, who was involved in the Danish-Lower Saxon War and tasked George Frederick with stopping the advance of Wallenstein into northern Germany.When Wallenstein approached, George Frederick withdrew to the island of Poel and then to Heiligenhafen in Holstein.