The Grey League () was founded in 1395 in the Upper Rhine valley, as a reaction to various feuds between the Barony of Belmont, the Lordship of Sax, the Barony of Rhäzüns, the Barony of Vaz, County of Werdenberg, Disentis Abbey and the Bishopric of Chur.
Even before 1440, the lordships of Löwenberg, Thusis, Tschappina and Heinzenberg joined the League, despite the count of Werdenberg-Sargans having forbidden them from doing so.