In May 1625 Christian IV of Denmark, Duke of Holstein was elected – in the latter of his functions – by the Lower Saxon Circle's member territories commander-in-chief of the Lower Saxon troops. More troops were recruited and to be billeted and alimented in the Lower Saxon territories, including the Prince-Archbishopric. In the same year "Christian IV" joined the Anglo-Dutch war coalition. In 1625 "Tilly" warned the Prince-Archbishop "John Frederick" to further accept the stationing of Danish troops and Ferdinand II, Holy Roman Emperor, demanded the immediate end of his and "Verden's" alliance with Denmark, with "Verden" being already ruled by "Christian's" son "Frederick", being as well the provided successor of "John Frederick". He declared again his loyalty to the Emperor and neutrality in the conflict. But all in vain.