After the Peace of Augsburg in 1555, the Countess of Mansfield, Agnes von Mansfeld-Eisleben (a Protestant canoness at the Abbey of Gerresheim to the east) converted Gebhard Truchsess von Waldburg, the Archbishop-Elector of Cologne to Calvinism. Their marriage and his declaration of religious parity throughout his lands caused another round of religious war, the Cologne War. The couple fled numerous times through various German states before Gerhard relinquished his claims in 1588. He died and was buried in Strassbourg in 1601, having failed in his attempt to convert his electorate into a dynasty. His lady (who could not return to the convent) came under the protection of the Dukes of Württemberg and died in 1601, terminating the family's Mittelort branch.