The original Lucerne Sword was found in the Lake of Lucerne in Switzerland. The find condition was poor, with a lot of pitting beneath the patina.
The sword is a Type: XVa with pommel type J, crossguard style 8 and dates to c. 1350-1370. It is now in the Royal Armouries Collection.
This form of sword seems to have been fashionable in the 14th century, judging by the number of survivors.
It has the look of our Historical Black Prince but with more of a distill taper in the blade, and fine curves in the pommel as you will see below.
The Battle of Sempach was fought very near this lake, July 9, 1386 between Duke Leopold III of Austria and the Swiss Confederation. Leopold assembled his army at Sursee, about 5 miles down from Sempach, surrounded Sempach and on the same day started to march towards the expected relief army. He did not take the direct route to Lucerne, but rather turned east. He must have known that an enemy army was approaching from there.
The Confederation army had presumably assembled at the bridge over the Reuss River at Gislikon. It marched from there, hoping to catch Leopold still at Sempach where he could be pressed against the lake. Around noon, the two armies made contact near Sempach, close to the village of Hildisrieden.
As the knights of Leopold's army approached, they dismounted and sought to storm the high ground. Their marksmen then took the Swiss under heavy fire. Leopold reasonably believed that the Swiss army lay before him, and engaged in battle before his rear units moved up from the approaching column. But it was only the confederate's advance guard that they were fighting.