be the ruler of the bishopric. Since he was Lutheran, the Holy See denied him the title of bishop. Nevertheless, he and later administrators were often referred to as prince-bishops. Frederick II was a son of King Christian IV of Denmark and Norway. In 1626, Christian IV, who was also Duke of Holstein, and thus a vassal of the Emperor, joined the anti-imperial coalition of the Republic of the Seven United Netherlands and the Kingdom of England under James I. After Christian IV was defeated at the Battle of Lutter am Barenberge, on 27 August 1626, by the troops of the Catholic League under Johan 't Serclaes, Count of Tilly, he and his remaining troops fled to the Prince-Archbishopric of Bremen and set up headquarters in Stade. Administrator John Frederick, Duke of Schleswig-Holstein-Gottorp, who was also Administrator of the Prince-Bishopric of Lübeck, fled to Lübeck and left the Prince-Archbishopric to be ruled by the Chapter and the Estates. In 1626, Tilly and his Catholic League troops occupied Verden, causing the Lutheran clergy to flee. He demanded that the Chapter of Bremen allow him to enter the Prince-Archbishopric and while the Chapter declared its loyalty to the Emperor, it delayed an answer to the request, arguing that it had to consult in a diet with the Estates, which would be a lengthy procedure. Meanwhile, Christian IV arranged for Dutch, English and French troops to land in Bremen. The Chapter's pleas for a reduction of the contributions, Christian IV commented by arguing once the Leaguists would take over, his extortions will seem little. In 1627, Christian IV withdrew from the Prince-Archbishopric of Bremen, in order to fight Wallenstein's invasion of his Duchy of Holstein. Tilly then invaded Bremen and captured its southern parts. The city of Bremen shut its city gates and entrenched behind its improved fortifications. In 1628, Tilly besieged Stade with its remaining garrison of 3,500 Danish and English soldiers. On 5 May 1628 Tilly granted them safe-conduct to England and Denmark-Norway and the whole of ecclesiastical Bremen was in his hands. Now Tilly turned to the city of Bremen, which paid him a ransom of 10,000 rixdollars in order to save itself from a siege. The city remained unoccupied. The populations in both prince-bishoprics were subjected to measures of "re-Catholicisation" within the scope the Counter-Reformation, with Lutheran services suppressed and Lutheran pastors expelled. In July 1630, Tilly and most