In the different historical struggles for expansion of territory or privileges and the concerned and disfavoured entity's defence against such annexation or usurpation, plenty of documents have been completely forged or counterfeited or backdated, in order to corroborate one's arguments.
Bremen's remaining suffragan sees at that time were only existing by name, since insurgent Wends had destroyed the so-called Wendish dioceses of Oldenburg-Lübeck, Ratzeburg and Schwerin and they were only to be reestablished later.
In 1168 the Saxon clan of the Ascanians, allies of Frederick I Barbarossa, had failed to install their family member Count Siegfried of Anhalt, on the see of Bremen.
The city reserved an extra very narrow gate, the so-called Bishop's Needle (Latin: Acus episcopi, first mentioned in 1274), for all clergy including the Prince-Archbishop.
The only thing they all had in common was, that the prior archbishops or capitulars or the Chapter as a collective obtained some secular power in them by way of purchase, application of force, usurpation, commendation, pledge, donation etc.
Almost everywhere the rule was to be shared with one or more competing bearers of authority, e.g. aristocrats, outside ecclesiastical dignitaries, autonomous corporations of free peasants (German: Landsgemeinden) or chartered towns and the like.
The bishopric's Estates again were by no means homogenous and therefore often quarreled for they consisted of the hereditary aristocracy, the service gentry, non-capitular clergy, free peasants and burghers of chartered towns.
Schisms in Church and State marked the next two centuries, and in spite of the labours of the Windesheim and Bursfelde congregations, the way was prepared for the Reformation, which made rapid headway, partly because the last Roman Catholic prince-archbishop, Christopher the Spendthrift, was in permanent conflict with the Chapter and the Estates.
Lacking papal confirmation and imperial liege indult could bring a prince-bishop elect into the precarious situation to be dismissed by the Emperor or by any of his vassals powerful enough and keen to do so.
In return his father Francis I waived any Saxe-Lauenburgian claim to the Land of Wursten as well as to the district of Bederkesa and abandoned the lawsuit, which he had brought to the Imperial Chamber Court to this end.
The Holy See conveyed to the Nuncio to Cologne, Pietro Francesco Montoro, the task to look after the Nordic Missions in - among others - the Prince-Archbishopric of Bremen and the Prince-Bishopric of Verden.
After Henry's early death, Duke Adolf of Schleswig-Holstein-Gottorp wielded influence at the Bremian Chapter to elect his son John Adolphus of Schleswig-Holstein at Gottorp (*1575-1616*) to the See.
After 1613 King Christian IV of Denmark and Norway, being in personal union Duke of Holstein within the Holy Roman Empire, turned his attention to gain grounds by acquiring the prince-bishoprics of Bremen, Verden, Minden and Halberstadt.
In 1623 Christian's son succeeded the late Philip Sigismund as Frederick II, Administrator of the Prince-Bishopric of Verden, only to flee the troops of the Catholic League under Count Johan 't Serclaes of Tilly in 1626.
In November 1619 Christian IV of Denmark, Duke of Holstein stationed Danish troops in the Bremian city of Stade, officially on behalf of his son the provided to be Administrator successor, suppressing an unrest of its burghers.
The Administrator and the Estates of the Prince-Archbishopric met in a Diet and declared for their territory their loyalty to Ferdinand II, Holy Roman Emperor, and their neutrality in the conflict.
With Danish troops within his territory and Christian the Younger's request Administrator John Frederick tried desperately to keep his Prince-Archbishopric out of the war, being in complete agreement with the Estates and the city of Bremen.
The population suffered from billeting and alimenting Baden-Durlachian, Danish, Halberstadtian, Leaguist, and Palatine troops, whose marching through the Prince-Archbishopric had to tolerate in order to prevent entering into armed conflict.
The Chapter, now holding the baby, declared again its loyalty to the Emperor and delayed an answer to the request, arguing that it had to consult with the Estates in a Diet first, which would be a lengthy procedure.
The Leaguist takeover enabled Ferdinand II, Holy Roman Emperor, to implement the Edict of Restitution, decreed on 6 March 1629 within the Prince-Archbishopric of Bremen and the Prince-Bishopric of Verden.
The Bremian monasteries still maintaining Roman Catholic rite – Altkloster Convent, Harsefeld Archabbey [nds], Neukloster, and Zeven – became the local strongholds for a reCatholicisation within the scope of Counter-Reformation.
Under the threat of the Edict of Restitution John Frederick consented to Canonical Visitations of the remaining monasteries, those clinging to Roman Catholic rite and those converted to voluntary Lutheran convents alike.
So Ferdinand II himself dismissed him by way of using the Edict of Restitution, in favour of his youngest son, the Roman Catholic Archduke Leopold Wilhelm of Austria, already administrator of the prince-bishoprics of Halberstadt (1628–1648), Passau (1625–1662) and Strasbourg (1626–1662).
The anti-Catholic attitudes of the burghers and the council of Bremen would make it completely impossible to prepare the restitution of estates from the Lutheran Chapter to the Roman Catholic Church.
The city council answered under these circumstances it would rather separate from the Holy Roman Empire and join the quasi-independent Republic of the Seven Netherlands (Its independence was finally confirmed by the Treaty of Westphalia in 1648).
In July 1630 Tilly left to head for the Duchy of Pomerania, where King Gustavus II Adolphus of Sweden had landed with his troops, opening a new front in the Thirty Years' War.
In the same year Pope Urban VIII provided the Catholic coadjutor Leopold Wilhelm, Archduke of Austria, imposed in 1629 by his father Ferdinand II, with the Archdiocese of Bremen, but due to its persisting occupation by the Swedes he never gained de facto pastoral influence let alone the power as administrator of the prince-archbishopric.
Christian IV of Denmark had to sign the Second Peace of Brömsebro on 13 August 1645, a number of Danish territories, including the two prince-bishoprics, being ceded into Swedish hands.
Wartenberg never gained pastoral influence, let alone power as prince-bishop due to the persisting Swedish occupation of the Prince-Archbishopric until the end of the Thirty Years' War.
Except for the prevailingly Calvinist Free Hanseatic City of Bremen and its territory, which continued to be supervised by the Roman Catholic Vicariate Apostolic of the Nordic Missions.