One of the first acts of Henry VII. was to grant to the league the most ample confirmation of their sole dependence upon the Empire and complete exemption from all foreign jurisdiction. In return for this they sent three hundred soldiers to accompany the Emperor on his Italian campaign—the first occasion on which Swiss troops served outside their own country. In the struggle between Lewis the Bavarian and Frederick of Austria the confederates naturally adopted the side of the former. Leopold, Frederick’s brother, determined to punish the rebellious and audacious peasants, as he called them. There is a legendary account of the great battle between the opposing [Sidenote: Battle of Morgarten, 1315.] forces; but all that is known is that Leopold’s men-at-arms allowed themselves to be attacked in a narrow valley at Morgarten, where they had no room for evolution, and the Swiss, having first thrown them into confusion by a shower of stones and other missiles, routed them at the first down-hill charge. This is the first of the great fights which showed the Swiss to be invincible on their own ground, and trained them to become for a time the finest infantry in Europe. The victory was celebrated by the formal renewal of the league at the village of Brunnen; Lewis the Bavarian recognised the value of the service to his cause by confirming the edict of Henry VII.; and by a treaty in 1318 the Hapsburgs withdrew all claims to administrative authority within the limits of the Forest Cantons. The league was now a recognised and successful body to which its neighbours could look for aid in an emergency. The nearest, and for that reason the most important, of these neighbours was the town of Luzern, which had grown [Sidenote: Luzern joins the League, 1330.] up in the territory and under the protection of the abbey of Murbach. As the town grew in power and wealth, the direct ownership of the abbey was broken off, but the monks retained in their hands the appointment of chief magistrate until it was purchased from them by Rudolf of Hapsburg. The buying up of similar rights was one of the chief methods by which he sought to extend his ascendency in Swabia. From that time Luzern had acknowledged some measure of subjection to the Hapsburgs, and had aided them with men and money in their struggle with Lewis the Bavarian. But the demands of their overlords became more and more onerous, and growing discontent seems to have impelled the citizens to seek the support of the neighbouring villages. On December 7, 1330, Luzern was formally admitted to the league, and this completed the union of the four Forest Cantons.