Although there had been overtures under Archduke Albrecht in 1462–3 to conclude
a lasting peace with the Swiss which would embrace the whole of Outer Austria
from the Hegau to Alsace,58 Bilgeri von Heudorf ’s feud revealed how easily a local
incident could tumble into open warfare on the Hochrhein. Meanwhile, a fresh
zone of conflict had opened up in the west. The territorial nobility of Alsace had
long set its sights on the small imperial city of Mulhouse, an enclave in the Austrian
Sundgau. Repeated raids on the city drove it into the arms of the northern Swiss
city-states, Bern and Solothurn, who harboured territorial ambitions of their own,
leading to the conclusion of a formal treaty of protection for twenty-five years
in 1466.59
To compound the likelihood of war, the Swiss were perfectly aware that
Archduke Sigismund, despite Austria’s revived presence in Swabia, was effectively
bankrupt and therefore willing to trade territory for cash. In March 1467 he had
been obliged to mortgage Rheinfelden to Basel for 21,000 fl, much against the will
of its inhabitants,60 and in August that year he also pledged Winterthur, the last
Austrian enclave in the Thurgau, to Zürich for 10,000 fl.61 Sigismund was in effect
reprising some of Albrecht’s earlier plans to hand over all four Forest Towns—
Rheinfelden, Säckingen, Laufenburg, and Waldshut—to Basel as recompense for
the 26,000 fl which it had lent to Austria in 1449. At that time it was even mooted
that the whole of the Black Forest should be pledged or indeed sold to Basel,
though the latter option may have been no more than a crafty piece of debt
58 EA II, 325 (no. 514); Baum, Habsburger, 465–6.
59 EA II, 354–6 (no. 539); Baum, Habsburger, 495–6; Dorothea A. Christ, Zwischen Kooperation
und Konkurrenz. Die Grafen von Thierstein, ihre Standesgenossen und die Eidgenossenschaft im
Spätmittelalter (Zürich, 1998), 329.
60 Rheinfelden had become a refuge for Basel exiles. Added to that, there were ongoing disputes
over frontiers, customs, and shipping on the Rhine. Rudolf Wackernagel, Geschichte der Stadt Basel,
2/1 (Basel, 1911), 9.
61 Baum, Habsburger, 500–3; Baum, Sigmund, 217; Peter Niederhäuser, ‘Im Dialog mit der
Stadtherrschaft. Winterthur und Habsburg im ausgehenden Mittelalter’, in Romy Günthart and
Michael Jucker (eds), Kommunikation im Spätmittelalter. Spielarten—Wahrnehmungen—Deutungen
(Zürich, 2005), 91–9; Thomas Weibel, ‘Der Zürcher Stadtstaat’, in Geschichte des Kantons Zürich, 2:
Frühe Neuzeit: 16. bis 18. Jahrhundert, ed. Thomas Weibel (Zürich, 1996), 31. Austria made claims
into the 18th century to redeem the mortgage; in the meantime the town had been able to construct
a modest territory of its own. Werner Ganz, Winterthur: Einführung in seine Geschichte von den
Anfängen bis 1798 (292. Neujahrsblatt der Stadtbibliothek Winterthur, 1961) (Winterthur, 1960),
112–22.