Habsburg duke Leopold III of Austria leads an invasion of Switzerland to counterbalance the occupation of his territories by Swiss Confederation troops.

On July 9, 1386, near the village of Sempach, a column of Austrian heavy cavalry dismounts and rapidly forces the Swiss vanguard from Lucerne.

Legendary Swiss hero Arnold Winkelreid reputedly throws himself against the Austrian line, drawing many of its spears to his breast.

Although he is killed, he thus creates an opening in the line that enables the main forces of the confederation—infantry armed with pikes and halberds‚ to defeat the dismounted column, then slaughter a second dismounted column before it can organize and advance.

A third Austrian column flees, and Leopold, together with all his dismounted knights, dies in the battle.