Niederhessen
Landgrave Louis I of Hesse decisively won the Mainz-Hesse War of 1427 with a victory against Mainz' commander Gottfried of Leiningen in the Battle on the Großenenglise Plateau near Fritzlar on July 23 and against Archbishop Conrad III himself at Fulda on August 10, Louis established his territorial supremacy in Upper and Lower Hesse. This meant that Ziegenhain could no longer lean on Mainz to retain its independence from Hesse. Instead, John II concluded a defensive alliance with Hesse on 29 June 1428, that made Ziegenhain virtually a Hessian dependency. This brought Hesse much closer to its goal of annexing Ziegenhain and thereby connecting Upper and Lower Hesse geographically.