Lower Hesse
In 1324, Archbishop Matthias of Mainz escalated his feud against Otto I of Hesse. This feud was originally about Lower Hesse, which had been held by Otto's half-brother John, Landgrave of Lower Hesse as a fief from Mainz. When John of Lower Hesse died childless in 1311, Lower Hesse fell to Otto. The archbishops of Mainz disagreed, arguing that as John had no sons, Lower Hesse should fall back to Mainz as a completed fief.