Swiss-Austrian border

The modern states of Austria and Switzerland share a border with a length of 180 km in two parts, separated by Liechtenstein, the longer stretch running across the Grison Alps and the shorter one following the Alpine Rhine to its mouth at Lake Constance.

The current border was a product of the creation of the Helvetic Republic in 1798. During the 19th century it was part of the western border of the Austrian Empire and later Austria-Hungary, and in the 20th century of the First Austrian Republic, the Federal State of Austria, of Nazi Germany and Allied-occupied Austria, and eventually of modern Austria since its formation in 1955. Liechtenstein was created as an independent principality with the Peace of Pressburg (1805) although it remained nominally a member of the Confederation of the Rhine until 1866).

The border ultimately reflects the success of the various rivals of the House of Habsburg (most notably the Old Swiss Confederacy and the Three Leagues) in limiting the influence of the Habsburg Archdukes of Austria in the original Habsburg domains west of the Rhine in the 14th to 15th centuries. Most of the Alpine part of the border had already been the outer border of the Three Leagues since the 15th century (with the exception of the Vinschgau, which was acquired by Austria only in 1499, and remained disputed territory into the 18th century). By contrast, the Alpine Rhine Valley has a complicated feudal history (partly acquired by the Counts of Toggenburg during the 14th and 15th centuries), but the territories on its left bank had become subject territories of the Swiss Confederacy by the 17th century.

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Wikipedia