West Pomerania’s part in the war for the throne of the Archbishop of Magdeburg in 1277–1283

15 January 1277 saw the death of Archbishop of Magdeburg Conrad von Sternberg, who had an inimical attitude towards the Margraves of Brandenburg from the Johannine line1. Among the several things that negatively affected the Archbishop’s relations with the sons of John I: John II, Otto IV and Conrad, was the fact that they supported the ecclesiastical career of their brother Eric, canon of the Monastery in Halberstadt. They determinedly and stubbornly promoted their brother to important positions in the chapter in Magdeburg. From 1264, he held the prebend in Magdeburg. The successive steps of his well-planned church career were to lead him, first to the office of bishop coadjutor and then to the throne of the Archbishops of Magdeburg. The Johannine margraves made an attempt to strengthen Eric’s position in the structure of the chapter in Magdeburg as early as in 1272. Their actions led to a sharp conflict and a war with the incumbent archbishop Konrad von Sternberg and his allies. On 1 May 1272, Archbishop Konrad made a pact with Lord Nicholas of Werle, Count Gunzelin of Schwerin, Lord Henry of Mecklenburg, and Waldemar of Rostock and his sons that they would support the archbishop with all their might