Treaty of Bromberg
... that in the Treaty of Bromberg, Poland-Lithuania accepted Hohenzollern sovereignty in the Duchy of Prussia in turn for an "eternal alliance"?
... that in the <b id="mwAp4"><a href="./Treaty_of_Bromberg" id="mwAp8" rel="mw:WikiLink" title="Treaty of Bromberg">Treaty of Bromberg</a></b>, <a class="mw-redirect" href="./Polish-Lithuanian_Commonwealth" id="mwAqA" rel="mw:WikiLink" title="Polish-Lithuanian Commonwealth">Poland-Lithuania</a> accepted <a href="./House_of_Hohenzollern" id="mwAqE" rel="mw:WikiLink" title="House of Hohenzollern">Hohenzollern</a> sovereignty in the <a href="./Duchy_of_Prussia" id="mwAqI" rel="mw:WikiLink" title="Duchy of Prussia">Duchy of Prussia</a> in turn for an "eternal alliance"?