 In May 1625, Duke Christian IV 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.In the same year Christian IV joined the Anglo-Dutch military coalition.Christian IV ordered his troops to capture all the important traffic hubs in the Prince-Archbishopric and commenced the Battle of Lutter am Barenberge, on 27 August 1626, where he was defeated by the Leaguist troops under Johan 't Serclaes, Count of Tilly.