Die Eidgenossen von Schwyz, Unterwalden, Luzern, Zürich, Zug und Glarus ziehen gegen das Städtchen Weesen am Walensee (1386?)
The Confederates of Schwyz, Unterwalden, Lucerne, Zurich, Zug and Glarus move against the town of Weesen on Lake Walen (1386?)
Wikipedia Page on Weesen / Location on Google Maps / Battle of Näfels (to which this is a prelude)
On the history of the flag of Schwyz
Nihil sub sole novum 