Burgdorferkrieg

The Burgdorferkrieg (German: Burgdorf war) or Kyburgerkrieg (German: Kyburg war) was a war in 1383-84 between the counts of Neu-Kyburg and the city of Bern for supremacy in the County of Burgundy in what is now Switzerland.

The counts of Kyburg were a medieval noble family in central and northern Switzerland and Swabia. Throughout the 12th and 13th centuries they had expanded in power and influence. In 1250/51 the childless Hartmann IV of Kyburg gave the western part of the property with the center of Burgdorf to his nephew Hartmann V. After Hartmann V's death Count Rudolf von Habsburg took over the administration of the western section of the Kyburg lands and eventually reunited them. The family of Neu-Kyburg began to rule the united Kyburg lands as Habsburg vassels. In 1322, the brothers Eberhard II and Hartmann II of Neu-Kyburg started fighting with each other over who would inherit the undivided lands. The fighting led to the "fratricide at Thun Castle" where Eberhard killed his brother Hartmann. To avoid punishment by his Habsburg overlords, Eberhard fled to Bern. In the following year, he sold the town of Thun, its castle and the land surrounding Thun to Bern. Bern granted the land back to Eberhard as a fief and the Neu-Kyburgs became connected to Bern, but was often in conflict with the city.

In the 14th century, the Neu-Kyburgs became increasingly indebted. On 11 November 1382, Count Rudolf II of Neu-Kyburg, launched a raid against the city of Solothurn to try and force the city to forgive his debts. For the city of Bern, this attack on an allied represented an excellent opportunity for the city to break its ties with the Neu-Kyburgs.

The city prepared by acquiring loans from Basel and weapons from Lucerne. They convinced the Neu-Kyburg's patron, the Austrian Duke Leopold III of Habsburg to not interfere. They then got promises of military support from Savoy, Neuchâtel and for the first time, based on the Federal Charter of 1353, the Swiss Confederation.

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