On November 15 1315, the soldiers of Duke Leopold I of Austria were thoroughly defeated by an ambush of the Swiss Confederation near the Morgarten pass.
The Habsburg house still coveted the countries around the Gotthard pass to secure this shortest passage to Italy, while the Confederates of Uri, Schwyz and Unterwalden had imperial freedom letters from former emperors granting them local autonomy within the empire.
At the time, the crown of the Holy Roman Emperor was claimed by both Duke Louis IV of Bavaria (who was to become Louis IV, Holy Roman Emperor) and Frederick the Handsome, a Habsburg prince. The Confederates supported Louis IV because they feared the Habsburgs would annex their countries as Habsburg property which they already had tried in the late 13th century.
The actual occasion for the war was a dispute between the Confederates of Schwyz and the Habsburg-protected monastery of Einsiedeln regarding some pastures, and was eventually triggered by a raid of the monastery by the Confederates of Schwyz.
Frederick's Brother, Leopold of Austria, led an army of 3000 to 5000 men, about one third of them knights on horseback to crush the rebellious confederates, planning a surprise attack from south via lake Aegeri and the Morgarten pass and counting on a complete victory over the rebellious peasants.
The Confederates of Schwyz, supported by the Confederates of Uri, who feared for their autonomy, but not supported by the Confederates of Unterwalden, expected the army in the west near the village of Arth , where they had erected fortifications. A historically plausible legend tells of the Knight of Huenenberg who shot an arrow into the camp of the Confederates with the attached message "watch out on St. Otmar's day at the Morgarten".
The Confederates prepared a road block and an ambush at a point between lake Aegeri and Morgarten pass where the small path led between the steep slope and a swamp. When about 1500 men attacked from above with rocks, logs and halberds, the knights had no room to defend themselves and were crushingly defeated, while the foot soldiers in the rear fled back to the city of Zug. The Confederates, not familiar with the customs of battles between knights, were described by a chronist as brutally butchering everything that moved and was unable to flee. This founded the reputation of the Confederates as barbarian, yet fierce and respectable fighters.
The confederates renewed their oath and within the next forty years cities like Lucerne, Zug, Zürich and Berne joined the confederation.
The victory of the confederates left them in their virtual autonomy and gave them a breathing space of some sixty years before the next Habsburg attack, the Battle of Sempach.
